Methods for treating ocular surface pain

ABSTRACT

The present invention provides methods for treating ocular surface pain by administering 4-(7-hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile (compound I). The present invention also provides methods for treating dry eye disease and ocular hyperemia by administering 4-(7-hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile.

REFERENCE TO RELATED APPLICATIONS

The application is a continuation of U.S. application Ser. No. 16/789,963, filed Feb. 13, 2020, which claims priority to U.S. Provisional Application No. 62/806,682, filed Feb. 15, 2019 which is incorporated herein in its entirety.

FIELD OF THE INVENTION

The present disclosure relates to methods for treating ocular surface diseases or disorders using 4-(7-Hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile (compound I).

BACKGROUND OF THE INVENTION

The ocular surface, particularly the cornea, is densely innervated by sensory nerves. The activity of corneal nerves can be modified by inflammation caused by a number of factors, such as osmotic stress and tissue damage, as well as nerve injuries of the ocular surface. Ocular surface symptoms are the alarm system to indicate an imbalanced ocular surface homeostasis resulting in chronic ocular surface pain due to continuous stimuli causing stress and sensitization of the ocular surface.

Patients suffering from ocular surface pain, particularly chronic ocular surface pain have a significant decline in quality of life. In utility studies to date, the burden of severe chronic ocular surface pain has been likened to moderate to severe angina, dialysis, or disabling hip fracture. Severe chronic ocular surface pain as also been associated with depression and suicidal ideation. In many patients, the ocular surface pain remains unresolved despite treatment of the underlying pathology (e.g., recent trauma or surgery, infection, or inflammation). Morepover, treatments that are used for short term management of ocular pain (e.g., nonsteroidal anti-inflammatory drugs, steroids,) cannot be used for long term therapy. Thus, there is a long-felt and unmet need for safe, effective treatments for the treatment of ocular surface pain, particularly chronic ocular surface pain, when there are no other options to improve patients' quality of life, or to supplement current treatments.

SUMMARY OF THE INVENTION

In one embodiment, the present disclosure provides a method of treating ocular surface pain in a subject in need thereof, comprising ocularly administering an effective amount of 4-(7-Hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile (Formula I) having structure:

or a salt, solvate, polymorph, or co-crystal thereof to the subject.

In some embodiments, the ocular surface pain is episodic or acute pain. In some embodiments, the ocular surface pain is chronic ocular surface pain (COSP), lasting for at least about three months.

In some embodiments, the compound of formula I is administered to the cornea of the subject. In some embodiments, compound of formula I is administered to the subject at a concentration of about 0.5% w/v to about 3.5% w/v, about 0.5% w/v to about 2.5% w/v, or about 0.5% w/v to about 1.5 w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, or about 0.5% to about 2.5% w/v. In particular embodiments, the compound of formula I is administered at a concentration of about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v. In some embodiments, compound of formula I is administered to the subject at a concentration of about 5 mg/ml to about 35 mg/ml, about 5 mg/ml to about 25 mg/ml, or about 5 mg/ml to about 15 mg/ml, about 5 mg/ml to about 30 mg/ml, about 10 mg/ml to about 25 mg/ml, about 15 mg/ml to about 30 mg/ml, or about 5 mg/ml to about 25 mg/ml. In particular embodiments, the compound of formula I is administered at a concentration of about 5 mg/ml, about 10 mg/ml, about 15 mg/ml, about 20 mg/ml, about 25 mg/ml, about 30 mg/ml, or about 35 mg/ml.

In some embodiments of the methods to treat ocular surface pain described herein, the COSP is associated with dry eye disease. In some embodiments, the administration results in a decrease in the symptoms of dry eye disease. In particular embodiments, the administration results in a decrease in the ocular pain associated with dry eye disease. In some embodiments, the administration results in reduced incidence of at least about 10% in one or more of ocular dryness, ocular discomfort, ocular hyperemia, ocular burning or stinging, grittiness or foreign body sensation, or photophobia.

In some embodiments of the methods to treat ocular surface pain described herein, the subject suffers from one or more of dry eye disease, Sjogren's Syndrome, conjunctivitis (including keratoconjuctivitis, vernal keratoconjunctivitis, allergic conjunctivitis), Map-Dot-Fingerprint Dystrophy, acanthamoeba, fibromyalgia, Meibomian gland dysfunction, thyroid eye disease, rosacea, ptosis, keratoconus, ocular pain syndrome, Steven-Johnson's syndrome, corneal epitheliopathies, corneal neuropathies (including LASIK induced corneal neuropathies), corneal dystrophies (including recurrent corneal dystrophies), epithelial basement membrane dystrophy, corneal erosions or abrasions (including recurrent corneal erosions or abrasions), ocular surface diseases, blepharitis, graft vs host disease, meibomitis, glaucoma, conjunctivochalasis, keratopathis (including herpetic keratopathy, filamentary keratopathy, band or bullous keratopathy, exposure keratopathy), keratitis (including herpes simplex virus keratitis), iritis, episclentis, corneal surgery, multiple sclerosis, trichiasis, pterygium, neuralgia, xerophthalmia, or patients recovering from neurotrophic keratitis. In some embodiments of the methods described herein, the subject suffers from ocular pain persisting for at least three months after photorefractive keratectomy (PRK) surgery or laser-assisted in situ keratomileusis (LASIK) surgery.

In some embodiments, the methods to treat ocular surface pain described herein include administering an additional therapeutic agent to the subject.

In some embodiments of the methods to treat ocular surface pain described herein, the administration of compound I to the subject results in a reduction in a pain score of at least about 3, at least about 4, at least about 5, at least about 6, at least about 7, at least about 8, at least about 9 or at least about 10, compared to a placebo, when measured on a visual analog scale (VAS). In further embodiments, the administration of compound I to the subject results in a reduction in the subject's pain score of at least about 6, at least about 7, at least about 8, at least about 9 or at least about 10, compared to a placebo, when measured on the VAS.

In some embodiments of the methods to treat ocular surface pain described herein, the administration of compound I to the subject results in a reduction in the subject's pain of at least about 10%, at least about 15%, at least about 20%, or at least about 25%, compared to a placebo. In some embodiments, the reduction in the pain score arises from the difference in pain scores prior to and after administration of compound I to the subject. In some embodiments of the methods described herein, the administration of compound I to the subject the reduction in pain score occurs within about half hour after administration of compound I to the subject.

In some embodiments of the methods to treat ocular surface pain described herein, the administration of compound I to the subject results in a reduction in hyperemia in the subject of at least about 1, at least about 2, at least about 3, at least about 4, or at least about 5, on the McMonnies scale.

In some embodiments of the methods to treat ocular surface pain described herein, the administration of compound I to the subject does not result in a change in one or more of best corrected visual acuity, slit-lamp biomicroscopy, dilated eye exam, blink rate, tear production, intraocular pressure, compared to a placebo.

In some embodiments of the methods to treat ocular surface pain described herein, the compound of formula I is administered for at least about one, at least about two, or at least about three months. In some embodiments, the compound of formula I is administered for greater than 3 months. In some embodiments, the compound of formula I is administered one to four times daily. In particular embodiments, the compound of formula I is administered one or two times daily.

In some embodiments, the present disclosure relates to a compound of formula I

or a salt, solvate, polymorph, or co-crystal thereof, for use in the treatment or reduction of ocular surface pain.

In some embodiments, the ocular surface pain is acute or episodic ocular surface pain. In some embodiments, the ocular surface pain is chronic ocular surface pain lasting for at least 1 month, at least 2 months, or at least 3 months.

In some embodiments of the uses described herein, the compound of formula I is administered at a concentration of about 0.5% w/v to about 3.5% w/v, about 0.5% w/v to about 2.5% w/v, or about 0.5% w/v to about 1.5 w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, or about 0.5% to about 2.5% w/v.

In some embodiments of the uses described herein, the compound of formula I is administered at a concentration of about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v.

In some embodiments, the present disclosure relates to a medicine for treating or reducing ocular surface pain containing an active ingredient that is a compound of formula I

or a salt, solvate, polymorph, or co-crystal thereof.

In some embodiments, the ocular surface pain is acute or episodic ocular surface pain. In some embodiments, the ocular surface pain is chronic ocular surface pain lasting for at least 1 month, at least 2 months. In some embodiments, the ocular surface pain is chronic ocular surface pain lasting for at least 3 months. In some embodiments, the compound of formula I is administered at a concentration of about 0.5% w/v to about 3.5% w/v, about 0.5% w/v to about 2.5% w/v, or about 0.5% w/v to about 1.5 w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, or about 0.5% to about 2.5% w/v. In some embodiments, the compound of formula I is administered at a concentration of about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v.

In some embodiments, the disclosure relates to the use of a compound of formula I

or a salt, solvate, polymorph, or co-crystal thereof in the manufacture of a medicament for the treatment or reduction of ocular surface pain.

In some embodiments, the use of compound I is for acute or episodic ocular surface pain. In some embodiments, the use of compound I is for chronic ocular surface pain lasting for at least 1 month, at least 2 months, or at least 3 months.

In some embodiments of the uses described herein, the compound of formula I is administered at a concentration of about 0.5% w/v to about 3.5% w/v, about 0.5% w/v to about 2.5% w/v, or about 0.5% w/v to about 1.5 w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, or about 0.5% to about 2.5% w/v.

In some embodiments of the uses described herein, the compound of formula I is administered at a concentration of about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v.

In some embodiments, the disclosure relates to a method of reducing ocular surface pain in a subject in need thereof, comprising ocularly administering 4-(7-Hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile (Formula I) having structure:

or a salt, solvate, polymorph, or co-crystal thereof to the subject; wherein the compound of formula I is administered at a concentration of about 0.5% w/v to about 3.5% w/v, about 0.5% w/v to about 2.5% w/v, or about 0.5% w/v to about 1.5 w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, or about 0.5% to about 2.5% w/v.

In some embodiments, the ocular surface pain is acute or episodic ocular surface pain. In some embodiments, the ocular surface pain is chronic ocular surface pain lasting for at least 1 month, at least 2 months, or at least 3 months.

In some embodiments of the methods to reduce ocular pain described herein, the COSP is associated with dry eye disease.

In some embodiments of the methods to reduce ocular surface pain described herein, the administration of compound I to the subject results in a decrease in the symptoms of dry eye disease.

In some embodiments of the methods to reduce ocular surface pain described herein, the administration of compound I to the subject results in a decrease in the ocular pain associated with dry eye disease. In some embodiments of the methods described herein, the administration of compound I to the subject results in reduced incidence of at least about 10% in one or more of ocular dryness, ocular discomfort, ocular hyperemia, ocular burning or stinging, grittiness or foreign body sensation, or photophobia.

In some embodiments, the subject in need of reducing ocular surface pain suffers from one or more of dry eye disease, Sjogren's Syndrome, conjunctivitis (including keratoconjuctivitis, vernal keratoconjunctivitis, allergic conjunctivitis), Map-Dot-Fingerprint Dystrophy, acanthamoeba, fibromyalgia, Meibomian gland dysfunction, thyroid eye disease, rosacea, ptosis, keratoconus, ocular pain syndrome, Steven-Johnson's syndrome, corneal epitheliopathies, corneal neuropathies (including LASIK induced corneal neuropathies), corneal dystrophies (including recurrent corneal dystrophies), epithelial basement membrane dystrophy, corneal erosions or abrasions (including recurrent corneal erosions or abrasions), ocular surface diseases, blepharitis, graft vs host disease, meibomitis, glaucoma, conjunctivochalasis, keratopathis (including herpetic keratopathy, filamentary keratopathy, band or bullous keratopathy, exposure keratopathy), keratitis (including herpes simplex virus keratitis), iritis, episclentis, corneal surgery, multiple sclerosis, trichiasis, pterygium, neuralgia, xerophthalmia, or patients recovering from neurotrophic keratitis.

In some embodiments, the methods to reduce ocular surface pain described herein include administering an additional therapeutic agent to the subject.

In some embodiments of the methods to reduce ocular surface pain described herein, the administration of compound I to the subject results in a reduction in the subject's pain score of at least about 3 as compared to a pain score prior to administration of the compound, when measured on a visual analog scale (VAS). In some embodiments of the methods described herein, the administration of compound I to the subject results in a reduction in a pain score of at least about 3, at least about 4, at least about 5, at least about 6, at least about 7, at least about 8, at least about 9 or at least about 10, compared to a placebo, when measured on a visual analog scale (VAS). In some embodiments of the methods described herein, the administration of compound I to the subject results in a reduction in the subject's pain score of at least about 6, at least about 7, at least about 8, at least about 9 or at least about 10, compared to a placebo, when measured on the VAS.

In some embodiments of the methods to reduce ocular surface pain described herein, the administration of compound I to the subject results in a reduction in the subject's pain of at least about 10%, at least about 15%, at least about 20%, or at least about 25%, compared to a placebo. In some embodiments of the methods described herein, the reduction in the pain score arises from the difference in pain scores prior to and after administration of compound I to the subject.

In some embodiments of the methods to reduce ocular surface pain described herein, the administration of compound I to the subject results in a reduction in hyperemia in the subject of at least about 1, at least about 2, at least about 3, at least about 4, or at least about 5, on the McMonnies scale.

In some embodiments, the present disclosure relates to a method of reducing ocular hyperemia in a subject in need thereof, comprising ocularly administering 4-(7-Hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile (Formula I) having structure:

or a salt, solvate, polymorph, or co-crystal thereof to the subject; wherein the compound of formula I is administered at a concentration of about 0.5% w/v to about 3.5% w/v, about 0.5% w/v to about 2.5% w/v, or about 0.5% w/v to about 1.5 w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, or about 0.5% to about 2.5% w/v.

In some embodiments of the methods described herein, the administration of compound I to the subject results in a reduction in ocular hyperemia of at least about 1, at least about 2, at least about 3, at least about 4, or at least about 5, on the McMonnies scale. In some embodiments of the methods described herein, the administration of compound I to the subject results in reduced incidence of at least about 10% in one or more of ocular dryness, ocular discomfort, ocular burning or stinging, grittiness or foreign body sensation, or photophobia.

In some embodiments of the methods to reduce ocular hyperemia, the subject suffers from one or more of dry eye disease, Sjogren's Syndrome, conjunctivitis (including keratoconjuctivitis, vernal keratoconjunctivitis, allergic conjunctivitis), Map-Dot-Fingerprint Dystrophy, acanthamoeba, fibromyalgia, Meibomian gland dysfunction, thyroid eye disease, rosacea, ptosis, keratoconus, ocular pain syndrome, Steven-Johnson's syndrome, corneal epitheliopathies, corneal neuropathies (including LASIK induced corneal neuropathies), corneal dystrophies (including recurrent corneal dystrophies), epithelial basement membrane dystrophy, corneal erosions or abrasions (including recurrent corneal erosions or abrasions), ocular surface diseases, blepharitis, graft vs host disease, meibomitis, glaucoma, conjunctivochalasis, keratopathis (including herpetic keratopathy, filamentary keratopathy, band or bullous keratopathy, exposure keratopathy), keratitis (including herpes simplex virus keratitis), iritis, episclentis, corneal surgery, multiple sclerosis, trichiasis, pterygium, neuralgia, xerophthalmia, or patients recovering from neurotrophic keratitis.

Some embodiments of the methods described herein to reduce ocular hyperemia further include administering an additional therapeutic agent to the subject.

Specific preferred embodiments of the invention will become evident from the following more detailed description of certain preferred embodiments and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the model estimated mean (+/−SE) of visual analog scale (VAS) pain assessment over time (Primary PD analysis set). Any recorded VAS pain score at time points within 4 hours after the use of oral rescue medication (ORM) were replaced by the VAS record taken immediately before the use of ORM (per FDA guidance 2014). 20% of data were affected by use of ORM. Plotted means are least-squares means from primary efficacy model of VAS (range 0-100).

FIG. 2 shows a histogram of oral rescue medication use incidence (number of patients who did not use oral rescue medication) (Secondary PD analysis set). For each of the time periods, the right bar represents subjects who were administered compound I, while the left bar represents subjects who were administered vehicle. The percent of patients who did not use oral rescue medication (ORM) is presented in the y-axis. n/N represents the count/total number of patients at each treatment.

FIGS. 3A-3C provide the arithmetic mean (+/−SD) of ocular pain assessment survey (OPAS) over time for questions 4, 5, and 6 (Secondary PD analysis set). FIG. 3A provides the results from question 4: 24 hr Eye Pain When Most Painful (pain level), FIG. 3B provides results from Question 5: 24 hr Eye Pain When Least Painful (pain level), and FIG. 3C provides results from Question 6 24 hr Eye Pain On Average (pain level). For each of FIGS. 3A, 3B, and 3C, the dashed line with “x” represents vehicle, and the solid line with circles (∘) represents compound I.

FIGS. 4A-4D provide the arithmetic mean (+/−SD) of ocular pain assessment survey (OPAS) over time for questions 22, 23, 24 and 25 (Secondary PD analysis set). FIG. 4A provides results from Question 22: How Often Eye Pain With Redness (%). FIG. 4B provides results from Question 23: How Often Eye Pain With Burning (%). FIG. 4C provides results from Question 24: How Often Eye Pain With Sensitivity (%). FIG. 4D provides results from Question 25: How Often Eye Pain With Tearing (%). For each of FIGS. 4A, 4B, 4C, and 4D, the dashed line with “x” represents vehicle, and the solid line with circles (∘) represents compound I.

FIG. 5A provides the arithmetic mean (SD) plasma concentrations of compound I following topical ocular administration of 2.5% compound I (PK analysis set) on Day 1. FIG. 5B provides the arithmetic mean (SD) plasma concentrations of compound I following topical ocular administration of 2.5% compound I (PK analysis set) on Day 4.

FIG. 6A provides a bar chart of ocular hyperemia over time for compound I, FIG. 6B provides a bar chart of ocular hyperemia over time for Vehicle. The quadrants are S: Superior, N: Nasal, I: Inferior, and T: Temporal.

FIG. 7 provides the arithmetic mean (+/−SD) of epithelial defect size over time (Safety analysis set) Parameter (unit): Epithelial Wound Size (mm), Subcategory: Area (mm2). The dashed line with “x” represents vehicle, and the solid line with circles (∘) represents compound I.

DETAILED DESCRIPTION

“TRPV1 receptor” refers to the Transient Receptor Potential Vanilloid 1 that has been characterized through molecular cloning and pharmacology. See e.g., Caterina M J, et al., Nature 1997; 389:816-824. TRPV1 receptor activity is measured as described in WO2005/120510, hereby incorporated by reference in its entirety.

The language “effective amount” of the compounds described herein, refers to that amount of a therapeutic compound necessary or sufficient to perform its intended function within a mammal. An effective amount of the therapeutic compound can vary according to factors such as the amount of the causative agent already present in the mammal, the age, sex, and weight of the mammal, and the ability of the therapeutic compounds of the present disclosure to treat the ocular surface disorder and/or symptoms thereof in the mammal.

The phrase “ophthalmically compatible” refers to formulations, polymers and other materials and/or dosage forms which are suitable for use in contact with the ocular tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.

As used herein, the term “treat”, “treating” or “treatment” in connection to a disease or disorder refers in some embodiments, to ameliorating the disease or disorder (i.e., slowing or arresting or reducing the development of the disease or at least one of the clinical symptoms thereof). In another embodiment “treat”, “treating” or “treatment” refers to alleviating or ameliorating at least one physical parameter including those which may not be discernible by the patient. In yet another embodiment, “treat”, “treating” or “treatment” refers to modulating the disease or disorder, either physically, (e.g., stabilization of a discernible symptom), physiologically, (e.g., stabilization of a physical parameter), or both. In yet another embodiment, “treat”, “treating” or “treatment” refers to preventing or delaying the onset or development or progression of the disease or disorder or a symptom thereof.

As used herein, the term “subject” or “patient” refers to human and non-human mammals, including but, not limited to, primates, rabbits, pigs, horses, dogs, cats, sheep, and cows. In particular embodiments, a subject or patient is a human. In some embodiments, the term “patient” or “subject” refers to a human being who is diseased with the condition (i.e., disease or disorder) described herein and who would benefit from the treatment. As used herein, a subject is “in need of” a treatment if such subject (patient) would benefit biologically, medically or in quality of life from such treatment. In particular embodiments, the subject is an adult human at least about 18 years of age. In particular embodiments, the subject is an adult human from about 18 to about 75 years of age. In some embodiments, the subject is a human child up to about 18 years of age.

As used herein, “ocular surface” refers to the outer surface of the eye, which anatomically comprises the cornea (with epithelium, bowman layer, stroma, descement membrane, endothelium), conjunctiva, cul de sac, and the corneo-scleral junction, i.e., limbus.

As used herein, ocular administration includes administration to all parts of the eye including all parts of the ocular surface such as the cornea, conjunctiva, the cul de sac and the corneo-scleral junction, i.e., limbus.

As used herein, “pain” refers to constant or intermittent sensation of actual pain described as but not limited to stabbing, dull, sharp, or ache. Pain may also refer to similar related descriptors such as but not limited to burning, stinging, grittiness, foreign body sensation, dryness, sandy, tired, itchy, irritated, sensitivity to light.

As used herein, “ocular surface pain” refers to pain on the surface of the eye, e.g., cornea. Ocular pain may be nociceptive pain, which is generally caused by external physical or chemical damaging stimuli such as corneal surgery, inflammation, or other damage to the corneal surface. Ocular pain may also result from neuropathic pain, which may occur due to direct damage to the neurons of the body, resulting in messages of pain being sent to the central nervous system and brain regardless of the presence of noxious stimuli. As used herein “ocular surface pain” includes both nociceptive pain and neuropathic pain.

As used herein, the term “visual analog scale” (VAS) is a measure of pain intensity where a subject typically marks a place on a scale that aligns with their level of pain. The pain is marked in a range of “no pain” (score of 0) and “pain as bad as it could be” or “worst imaginable pain” (score of 100). See e.g., Hawker, et al., Arthritis Care & Research 63(11), pp. S240-S252 (November 2011). There are several other well-designed pain scales that may be used to help assess the extent of pain. The numerical rating scale (NRS) is often used, in which subjects use numbers to rate pain. The number scale may be from 1-10, or 1-100. The Wong-Baker FACES Pain Scale combines pictures and numbers for pain ratings. It can be used in children over the age of 3 and in adults. Six faces depict different expressions, ranging from happy to extremely upset. Each is assigned a numerical rating between 0 (smiling) and 10 (crying). The Verbal Pain Intensity Scale uses wordings on a scale to rate pain intensity: No Pain/Mild Pain/Moderate Pain/Severe Pain Very Severe Pain/Worst Possible Pain.

The Eye Sensation Scale is a specific pain scale was developed to measure ophthalmic pain severity. See Caudle L. E. et al., Optom Vis Sci. 2007 August; 84(8):752-62. In this scale, pain, discomfort or light sensitivity is typically measured by 5 category labels of “extreme,” “severe,” “moderate,” “mild,” or “none.”

The Ocular Pain Assessment Survey (OPAS) is a quantitative, multidimensional questionnaire, specifically designed for assessment of corneal and ocular surface pain and Quality of Life (QoL) changes. The OPAS assesses pain intensity, frequency of eye and non-eye pain, QoL changes, aggravating factors, associated factors, and symptomatic relief quantitative, allowing for monitoring of treatment responses. See Qazi et al., Ophthalmology July 123(7):1458-1468 (2016).

As used herein, the term “Visual Tasking Questionnaire” refers to a questionnaire that asks the subject to subjectively rate how much difficulty they have conducting certain activities that require a fixed or prolonged stare that may exacerbate ocular pain. The questionnaire also asks about coping mechanisms associated with the difficulties they experience during visual tasking activities.

As used herein, ocular hyperemia refers to redness of the ocular surface. Ocular hyperemia may be a clinical marker for inflammation and/or ocular irritation. Ocular hyperemia may be measured using the McMonnies scale, at values from 0 to 5, based on standard photographs.

As used herein, “placebo” refers to an ophthalmic formulation that includes all the components of the administered drug composition without the drug.

As used herein, the term “about” refers to a range of values+10% of a specified value.

As used herein, a pharmaceutical composition is a composition suitable for pharmaceutical use. A composition suitable for pharmaceutical use may be sterile, homogeneous and/or isotonic. Pharmaceutical compositions may be prepared in certain embodiments in an aqueous form, for example in a pre-filled syringe or other single- or multi-dose container. In certain embodiments of the invention, the pharmaceutical composition is ophthalmically compatible and suitable for ophthalmic administration to a human subject by, for example, topical or other known methods of delivery.

As used herein, “Compound of formula I,” “Compound I,” “Formula I,” and “compound I” are used interchangeably and mean a compound that has the name 4-(7-hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile, the structure shown below, and can be synthesized using procedures known in the art and described in WO2005/120510 and U.S. Pat. No. 8,349,852 (“Quinazolinone derivatives useful as vanilloid antagonists”) to Chen et al., both of which are hereby incorporated by reference in their entireties.

Additionally or alternatively, various crystalline and polymorphic forms of Compound I may be used.

In some embodiments, the compound I is in polymorphic form B, as described in U.S. Pat. No. 8,349,852, incorporated by reference herein. In some embodiments, polymorph B is characterized by an X-ray diffraction pattern having three or more peaks at 20 values selected from 9.3, 10.6 and 14.4.+−0.0.2° 2θ. In some embodiments, polymorph B is characterized by an X-ray diffraction pattern having three or more peaks at 20 values selected from 9.3, 10.6, 14.4, 15.5, 17.9, 19.9, 23.4.+−0.0.2° 2θ.

Any chemical formula given herein is also intended to represent unlabeled forms as well as isotopically labeled forms of the compounds. Isotopically labeled compounds have structures depicted by the formulae given herein except that one or more atoms are replaced by an atom having a selected atomic mass or mass number. Isotopes that can be incorporated into compounds of the disclosure include, for example, isotopes of hydrogen, carbon, nitrogen, and oxygen, such as ³H, ¹¹C, ¹³C, ¹⁴C, and ¹⁵N. Accordingly, it should be understood that methods of the present invention can or may involve compounds that incorporate one or more of any of the aforementioned isotopes, including for example, radioactive isotopes, such as ³H and ¹⁴C, or those into which non-radioactive isotopes, such as ²H and ¹³C are present. Such isotopically labelled compounds are useful in metabolic studies (with ¹⁴C), reaction kinetic studies (with, for example ²H or ³H), detection or imaging techniques, such as positron emission tomography (PET) or single-photon emission computed tomography (SPECT) including drug or substrate tissue distribution assays, or in radioactive treatment of patients. Isotopically-labeled compounds can generally be prepared by conventional techniques known to those skilled in the art, e.g., using an appropriate isotopically-labeled reagents in place of the non-labeled reagent previously employed.

The present invention encompasses embodiments that include all pharmaceutically acceptable salts of the compounds useful according to the invention provided herein. As used herein, “pharmaceutically acceptable salt” refers to derivatives of the disclosed compounds wherein the parent compound is modified by converting an existing acid or base moiety to its salt form. Examples of pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of basic residues such as amines; alkali or organic salts of acidic residues such as carboxylic acids; and the like. The pharmaceutically acceptable salts include the conventional non-toxic salts of the parent compound formed, for example, from non-toxic inorganic or organic acids. The pharmaceutically acceptable salts can be synthesized from the parent compound which contains a basic or acidic moiety by conventional chemical methods. Generally, such salts can be prepared by reacting the free acid or base forms of these compounds with a stoichiometric amount of the appropriate base or acid in water or in an organic solvent, or in a mixture of the two; generally, non-aqueous media like ether, ethyl acetate, ethanol, isopropanol, or acetonitrile are preferred. Lists of suitable salts are found in Remington's Pharmaceutical Sciences, 17^(th) ed., Mack Publishing Company, Easton, Pa., 1985, p. 1418 and Journal of Pharmaceutical Science, 66, 2 (1977), each of which is incorporated herein by reference in its entirety. For example, preferred pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of basic residues such as amines. For example, the salt can be a hydrochloride salt. Other examples of suitable salts can be found in U.S. Pat. No. 8,349,852, the content of which is hereby incorporated by its entirety.

The phrase “pharmaceutically acceptable” as employed herein refers to those compounds, materials, compositions, and/or dosage forms which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.

Compound (I) or a pharmaceutically acceptable salt thereof may be incorporated in various formulations for delivery. For example, topical formulations can be used and can include ophthalmically acceptable preservatives, surfactants, viscosity enhancers, buffers, sodium chloride, and water to form aqueous ophthalmically compatible solutions and suspensions.

The compound of formula I will normally be contained in these formulations in an amount from about 0.1% to about 5.0% w/v. In some embodiments, concentrations of compound I for topical administration range from about 0.5% to about 1.5% w/v, about 0.5% to about 2.5% w/v, about 0.5% to about 3.5% w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, about 0.5% to about 2.5% w/v. In some embodiments, the concentration of the compound of formula I in a formulation for topical use is at least about 0.5% w/v, at least about 1.0% w/v, at least about 1.5% w/v, at least about 2.0% w/v, or at least about 2.5% w/v. In some embodiments, the concentration of the compound of formula I in a formulation for topical use is no more than about 5.0% w/v, no more than about 4.5% w/v, no more than about 4.0% w/v, no more than about 3.5% w/v, or no more than about 3.0% w/v. In particular embodiments, the concentration of the compound of formula I in a formulation for topical use is about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v. It is commonly understood that equivalent concentrations can be expressed in different units. For example, a concentration of 0.1% w/v can also be expressed as a 1 mg/ml solution. Expressed in units of mg/ml, in some embodiments, compound of formula I is administered to the subject at a concentration of about 5 mg/ml to about 35 mg/ml, about 5 mg/ml to about 25 mg/ml, or about 5 mg/ml to about 15 mg/ml, about 5 mg/ml to about 30 mg/ml, about 10 mg/ml to about 25 mg/ml, about 15 mg/ml to about 30 mg/ml, or about 5 mg/ml to about 25 mg/ml. In some embodiments, the concentration of the compound of formula I in a formulation for topical use is at least about 5 mg/ml, at least about 10 mg/ml, at least about 15 mg/ml, at least about 20 mg/ml, or at least about 25 mg/ml. In some embodiments, the concentration of the compound of formula I in a formulation for topical use is no more than about 50 mg/ml, no more than about 45 mg/ml, no more than about 40 mg/ml, no more than about 35 mg/ml, or no more than about 30 mg/ml. In particular embodiments, the compound of formula I is administered at a concentration of about 5 mg/ml, about 10 mg/ml, about 15 mg/ml, about 20 mg/ml, about 25 mg/ml, about 30 mg/ml, or about 35 mg/ml.

In some embodiments, the formulations are delivered to the surface of the eye one to six times a day, depending on the routine discretion of the skilled clinician. In some embodiments, the formulations are administered, one, two, three, or four times a day.

Unless otherwise specified, the weight or dosage referred to herein for the compound of formula I is the weight or dosage of the compound itself, not that of a salt or prodrug thereof, which can be different to achieve the intended therapeutic effect. For example, the weight or dosage of a corresponding salt of a compound suitable for the methods, compositions, or combinations disclosed herein may be calculated based on the ratio of the molecular weights of the salt and compound itself.

Compound (I), and/or pharmaceutically acceptable salts thereof may be incorporated into ophthalmically compatible formulations for delivery to the eye. The compounds may be combined with ophthalmologically acceptable preservatives, surfactants, viscosity enhancers, penetration enhancers, buffers, sodium chloride, and water to form an aqueous, sterile ophthalmic suspension or solution.

The pharmaceutical compositions of the invention may include an additional therapeutic agent in addition to Compound (I). Further therapeutic agents may include, for instance, other compounds and antibodies useful for treating ocular surface disorders. A non-limiting list of such agents incudes nonsteroidal anti-inflammatory drugs such as ketorolac, nepafenac, bromfenac, corticosteroids; drugs for dry eye disease such as cyclosporine, lifitegrast, autologous serum, or other TRPV1 inhibitors. In particular embodiments, the additional therapeutic agent is an ophthalmic steroid such as dexamethasone, fluocinolone, loteprednol, difluprednate, fluorometholone, prednisolone, prednisone, medrysone, triamcinolone, betamethasone, rimexolone, or pharmaceutically acceptable salts thereof. Further non-limiting examples of such additional therapeutic agents that may be included in the pharmaceutical composition include Xiidra® (lifitegrast), Restasis® (cyclosporine), minocycline, doxycycline, or other tetracycline antibiotics. Other examples include keratolytic agents such as selenium disulfide, salicylic acid, glycolic acid etc., or pharmaceutically acceptable salts thereof.

Without being bound by theory, it is hypothesized that blockers of the Transient Receptor Potential Vanilloid 1 (TRPV1) receptor may be useful in the treatment of pain, e.g., chronic pain.

Accordingly, in some embodiments, the invention provides a method of treating ocular surface pain in a subject in need thereof, said method includes administering to the subject an effective amount of compound (I), or a pharmaceutically acceptable salt, solvate, or co-crystal thereof. In some embodiments, the invention provides a method of reducing ocular surface pain in a subject in need thereof, said method includes administering to the subject an effective amount of compound (I), or a pharmaceutically acceptable salt, solvate, or co-crystal thereof. In some embodiments, the invention provides for the use of the compound of formula I, or a pharmaceutically acceptable salt, solvate, or co-crystal thereof, in the treatment or reduction of ocular surface pain. In some embodiments, the compound of formula I is in polymorphic form B.

In some embodiments, the ocular surface pain is episodic, i.e., acute.

In some embodiments, the subject suffers from chronic ocular surface pain, which lasts for at least three months. In some embodiments, the subject suffers from chronic ocular surface pain, which lasts for at least two months. In some embodiments, the subject suffers from chronic ocular surface pain, which lasts for at least one month. In some embodiments, the subject suffers from chronic ocular surface pain, which lasts for at least four months. In some embodiments, the subject suffers from chronic ocular surface pain, which lasts for at least five months. Thus, in some embodiments, the invention provides a method of treating chronic ocular surface pain in a subject by administering to the subject an effective amount of compound of formula I, or a salt, solvate, polymorph, or co-crystal thereof. In some embodiments, the invention provides a method of reducing chronic ocular surface pain in a subject by administering to the subject an effective amount of compound of formula I, or a salt, solvate, polymorph, or co-crystal thereof. The invention provides for the use of the compound of formula I, or a pharmaceutically acceptable salt, solvate, polymorph, or co-crystal thereof, in the treatment of chronic ocular surface pain.

In some embodiments, the administration is to the ocular surface of the subject, e.g., any part of the cornea, conjunctiva, or to the cul de sac of the eye.

In some embodiments, the invention provides for the administration of the compound of formula I to a subject in need thereof in a ophthalmically compatible formulation at a concentration of about 0.5% w/v to about 3.5% w/v. In some embodiments, concentrations for administration range from about 0.5% to about 3.5% w/v, about 0.5% to about 2.5% w/v, about 0.5% to about 1.5% w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, about 0.5% to about 2.5% w/v. In particular embodiments, the concentration of the compound of formula I in a formulation for topical use is about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v. In some embodiments, compound of formula I is administered to the subject at a concentration of about 5 mg/ml to about 35 mg/ml, about 5 mg/ml to about 25 mg/ml, or about 5 mg/ml to about 15 mg/ml, about 5 mg/ml to about 30 mg/ml, about 10 mg/ml to about 25 mg/ml, about 15 mg/ml to about 30 mg/ml, or about 5 mg/ml to about 25 mg/ml. In particular embodiments, the compound of formula I is administered at a concentration of about 5 mg/ml, about 10 mg/ml, about 15 mg/ml, about 20 mg/ml, about 25 mg/ml, about 30 mg/ml, or about 35 mg/ml. In some embodiments, the dose per administration per eye is from about 0.15 to about 1.15 mg, or about 0.15 mg, 0.2 mg, about 0.25 mg, about 0.3 mg, about 0.35 mg, about 0.4 mg, about 0.45 mg, about 0.5 mg, about 0.55 mg, about 0.6 mg, about 0.65 mg, about 0.7 mg, about 0.75 mg, about 0.8 mg, about 0.85 mg, about 0.9 mg, about 0.95 mg, about 1.0 mg, about 1.05 mg, about 1.1 mg, or about 1.15 mg. In some embodiments, the dose per administration per eye is about 0.18 mg, about 0.37 mg, about 0.55 mg, about 0.74 mg, or about 0.92 mg. In some embodiments, the total daily dose per eye is about 0.5 to about 3.5 mg, or about 0.5 mg, about 1.0 mg, about 1.5 mg, about 2.0 mg, about 2.5 mg, about 3.0 mg, or about 3.5 mg. In some embodiments, the compound of formula I is administered to the subject one to six times a day, e.g., one, two, three, or four times a day. In some embodiments, the compound of formula I is administered to the subject for a period of at least about one month, at least about two months, or at least about three months. In some embodiments, the compound of formula I is administered to the subject for a period of at least about 12 weeks.

In some embodiments, the ocular surface pain or the chronic ocular surface pain is associated with one or more of dry eye disease, Sjogren's Syndrome, conjunctivitis (including keratoconjuctivitis, vernal keratoconjunctivitis, allergic conjunctivitis), Map-Dot-Fingerprint Dystrophy, acanthamoeba, fibromyalgia, Meibomian gland dysfunction, thyroid eye disease, rosacea, ptosis, keratoconus, ocular pain syndrome, Steven-Johnson's syndrome, corneal epitheliopathies, corneal neuropathies (including LASIK induced corneal neuropathies), corneal dystrophies (including recurrent corneal dystrophies), epithelial basement membrane dystrophy, corneal erosions or abrasions (including recurrent corneal erosions or abrasions), ocular surface diseases, blepharitis, graft vs host disease, meibomitis, glaucoma, conjunctivochalasis, keratopathis (including herpetic keratopathy, filamentary keratopathy, band or bullous keratopathy, exposure keratopathy), keratitis (including herpes simplex virus keratitis), iritis, episclentis, corneal surgery, multiple sclerosis, trichiasis, pterygium, neuralgia, xerophthalmia, or patients recovering from neurotrophic keratitis.

In particular embodiments, the ocular surface pain or the chronic ocular surface pain is associated with dry eye disease or Sjogren's Syndrome. In some embodiments of the methods described herein, the subject suffers from ocular pain persisting for at least three months after photorefractive keratectomy (PRK) surgery or laser-assisted in situ keratomileusis (LASIK) surgery.

In some embodiments, the subject suffers from conjunctivitis, subconjunctival hemorrhage, subconjunctival scarring, conjunctival membranes, conjunctival ulceration, superficial punctate epithelial erosions, epithelial defects, lid margin ulceration, lid margin keratinization, symblepharon, ankyloblepharon, trichiasis, anterior blepharitis, punctal auto-occlusion, meibomian gland disease, corneal opacification, dry eye, districhiasis, limbal stem cell failure, or corneal vascularization.

In some embodiments, the administration of compound of formula I results in a reduction in the subject's ocular pain, compared to a placebo. In some embodiments, the reduction in the subjects ocular pain is at least about 3 when measured on the VAS score, compared to a placebo. In some embodiments, the administration results in a reduction in the subject's ocular pain of at least about 4, at least about 5, at least about 6, at least about 7, at least about 8, at least about 9, or at least about 10, when measured on the VAS score, compared to a placebo. In some embodiments, the administration results in a reduction in the subject's pain of at least about 10%, at least about 15%, at least about 20%, or at least about 25%, compared to a placebo. In some embodiments, the administration results in a reduction in the subject's pain, when measured after 7 days of administration of the compound of formula I. In some embodiments, the administration results in a reduction in the subject's pain, when measured after 14 days of administration of the compound of formula I.

In some embodiments, the administration of the compound of formula I results in a reduction in the subject's pain of at least about 2 compared to a placebo, as measured by the VAS score, about half hour after the administration, about one hour, about 2 hours, or about 2-4 hours after the administration.

In some embodiments, the reduction in pain score arises from the difference in pain scores prior to and after administration of compound I to the subject. In some embodiments, the reduction in pain score as measured by the VAS, arises from the difference in pain scores prior to and after administration of compound I to the subject. In some embodiments, the reduction in pain score occurs within about half hour after administration of compound I to the subject. In some embodiments, the reduction in pain score occurs within about 1 hour, about 2 hours, about 3 hours, about 4 hours, about 5 hours, or about 6 hours after administration of compound I to the subject. In other embodiments, the reduction in pain score occurs after about 7 days of administration of compound I to the subject. In some embodiments, the reduction in pain score occurs after about 14 days of administration of compound I to the subject.

In some embodiments, the administration of the compound of formula I results in reduced ocular hyperemia (redness of the eye), compared to placebo. In particular embodiments, the administration of the compound of formula I results in reduced grade 1, grade 2, grade 3, or grade 4 hyperemia compared to placebo. In some embodiments, the administration results in a reduction in ocular hyperemia score of at least about 1, at least about 2, at least about 3, at least about 4, or at least about 5, on the McMonnies scale.

In some embodiments, the administration of the compound of formula I results in an improved score on at least one question of the OPAS of at least about 10%, at least about 20%, or at least about 30%.

In some embodiments, the administration of the compound of formula I results in an improved score on at least one question of the Visual Tasking Questionnaire of at least about 10%, at least about 20%, or at least about 30%.

Thus, in some embodiments, the present invention relates to a method of treating ocular hyperemia in a subject in need thereof, comprising administering to the subject an effective amount of compound of formula I, or a salt, solvate, polymorph, or co-crystal thereof. In some embodiments, the present invention relates to a method of reducing ocular hyperemia in a subject in need thereof, comprising administering to the subject an effective amount of compound of formula I, or a salt, solvate, polymorph, or co-crystal thereof. In some embodiments, the administration of compound I results in a reduction in ocular hyperemia of at least 1, at least 2, at least 3, at least 4, or at least 5 on the McMonnies scale. In some embodiments, the invention provides for the use of the compound of formula I, or a pharmaceutically acceptable salt, solvate, or co-crystal thereof, in the treatment of ocular hyperemia. In some embodiments, the invention provides for the administration of the compound of formula I to a subject in need thereof in a ophthalmically compatible formulation at a concentration of about 0.5% w/v to about 3.5% w/v. In some embodiments, concentrations for administration range from about 0.5% to about 3.5% w/v, about 0.5% to about 2.5% w/v, about 0.5% to about 1.5% w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, about 0.5% to about 2.5% w/v. In particular embodiments, the concentration of the compound of formula I in a formulation for topical use is about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v. It is to be understood that the percent values may be expressed in units of mg/ml. In some embodiments, the dose per administration per eye is from about 0.15 to about 1.15 mg, or about 0.15 mg, 0.2 mg, about 0.25 mg, 0.3 mg, about 0.35 mg, about 0.4 mg, about 0.45 mg, about 0.5 mg, about 0.55 mg, about 0.6 mg, about 0.65 mg, about 0.7 mg, about 0.75 mg, about 0.8 mg, about 0.85 mg, about 0.9 mg, about 0.95 mg, about 1.0 mg, about 1.05 mg, about 1.1 mg, or about 1.15 mg. In some embodiments, the dose per administration per eye is about 0.18 mg, about 0.37 mg, about 0.55 mg, about 0.74 mg, or about 0.92 mg. In some embodiments, the total daily dose per eye is about 0.5 to about 3.5 mg, or about 0.5 mg, about 1.0 mg, about 1.5 mg, about 2.0 mg, about 2.5 mg, about 3.0 mg, or about 3.5 mg. In some embodiments, the compound of formula I is administered to the subject one to six times a day, e.g., one, two, three, or four times a day. In some embodiments, the compound of formula I is administered to the subject for a period of at least about one month, at least about two months, or at least about three months.

In some embodiments, the ocular hyperemia is associated with one or more of dry eye disease, Sjogren's Syndrome, conjunctivitis (including keratoconjuctivitis, vernal keratoconjunctivitis, allergic conjunctivitis), Map-Dot-Fingerprint Dystrophy, acanthamoeba, fibromyalgia, Meibomian gland dysfunction, thyroid eye disease, rosacea, ptosis, keratoconus, ocular pain syndrome, Steven-Johnson's syndrome, corneal epitheliopathies, corneal neuropathies (including LASIK induced corneal neuropathies), corneal dystrophies (including recurrent corneal dystrophies), epithelial basement membrane dystrophy, corneal erosions or abrasions (including recurrent corneal erosions or abrasions), ocular surface diseases, blepharitis, graft vs host disease, meibomitis, glaucoma, conjunctivochalasis, keratopathis (including herpetic keratopathy, filamentary keratopathy, band or bullous keratopathy, exposure keratopathy), keratitis (including herpes simplex virus keratitis), iritis, episclentis, corneal surgery, multiple sclerosis, trichiasis, pterygium, neuralgia, xerophthalmia, or patients recovering from neurotrophic keratitis. In particular embodiments, the ocular hyperemia is associated with dry eye disease. In some embodiments of the methods described herein, the ocular hyperemia persists for at least three months after photorefractive keratectomy (PRK) surgery or laser-assisted in situ keratomileusis (LASIK) surgery.

In some embodiments, the ocular surface pain or chronic ocular surface pain is associated with dry eye disease. In some embodiments, the administration of the compound of formula I results in a decrease in the symptoms of dry eye disease. Dry eye disease is generally understood to be a complex, multifactorial condition characterized by inflammation of the ocular surface and lacrimal glands and reductions in the quality and/or quantity of tears. It is believed that up to 30% of dry eye disease patients suffer from ocular surface pain that may be chronic, i.e., lasting at least 12 weeks or three months. Thus, in some embodiments, the invention results in a decrease of at least about 10%, at least about 15%, at least about 20%, or at least about 30% in the symptoms of dry eye disease, including one or more of ocular dryness, ocular discomfort, ocular hyperemia, ocular burning or stinging, grittiness or foreign body sensation, or photophobia.

In some embodiments, the invention relates to a method of treating dry eye disease in a subject in need thereof, comprising administering to the subject an effective amount of compound of formula I, or a salt, solvate, polymorph, or co-crystal thereof. In some embodiments, the invention relates to a method of treating dry eye disease in a subject in need thereof, comprising administering to the subject an effective amount of compound of formula I, or a salt, solvate, polymorph, or co-crystal thereof, wherein the compound of formula I is safe for administration over a period of at least 2 months, at least 3 months, at least 4 months, or at least 5 months. In particular embodiments, the invention provides for the use of the compound of formula I, or a pharmaceutically acceptable salt, solvate, or co-crystal thereof, in the treatment of dry eye disease. In some embodiments, the invention results in a decrease of at least about 10% in the symptoms of dry eye disease, including one or more of ocular dryness, ocular discomfort, ocular hyperemia, ocular burning or stinging, grittiness or foreign body sensation, or photophobia. In some embodiments, the invention provides for the administration of the compound of formula I to a subject in need thereof in a ophthalmically compatible formulation at a concentration of about 0.5% w/v to about 3.5% w/v. In some embodiments, concentrations for administration range from about 0.5% to about 3.5% w/v, about 0.5% to about 2.5% w/v, about 0.5% to about 1.5% w/v, about 0.5% to about 3.0% w/v, about 1.0% to about 2.5% w/v, about 1.5% to about 3.0% w/v, about 0.5% to about 2.5% w/v. In particular embodiments, the concentration of the compound of formula I in a formulation for topical use is about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v. In some embodiments, the dose per administration per eye is from about 0.15 to about 1.15 mg, or about 0.15 mg, 0.2 mg, about 0.25 mg, 0.3 mg, about 0.35 mg, about 0.4 mg, about 0.45 mg, about 0.5 mg, about 0.55 mg, about 0.6 mg, about 0.65 mg, about 0.7 mg, about 0.75 mg, about 0.8 mg, about 0.85 mg, about 0.9 mg, about 0.95 mg, about 1.0 mg, about 1.05 mg, about 1.1 mg, or about 1.15 mg. In some embodiments, the dose per administration per eye is about 0.18 mg, about 0.37 mg, about 0.55 mg, about 0.74 mg, or about 0.92 mg. In some embodiments, the total daily dose per eye is about 0.5 to about 3.5 mg, or about 0.5 mg, about 1.0 mg, about 1.5 mg, about 2.0 mg, about 2.5 mg, about 3.0 mg, or about 3.5 mg. In some embodiments, the compound of formula I is administered to the subject one to six times a day, e.g., one, two, three, or four times a day. In some embodiments, the compound of formula I is administered to the subject for a period of at least about one month, at least about two months, or at least about three months.

In some embodiments of the methods described herein, the administration of the compound of formula I does not result in a change (e.g., of less than 5% difference, less than 4% difference, or less than 3% difference) in one or more of best corrected visual acuity, slit-lamp biomicroscopy, dilated eye exam, blink rate, tear production, intraocular pressure, compared to a placebo. In some embodiments of the methods described herein, the administration of compound of formula I does not result in a delay in wound healing compared to a placebo in a patient in need thereof.

Patient Population

In specific embodiments, a subject to be treated by methods provided herein suffers from an ocular surface disorder. Non-limiting examples of ocular surface disorders include chronic ocular surface pain (COSP), dry eye disease, Sjogren's Syndrome, conjunctivitis (including keratoconjuctivitis, vernal keratoconjunctivitis, allergic conjunctivitis), Map-Dot-Fingerprint Dystrophy, acanthamoeba, fibromyalgia, Meibomian gland dysfunction, thyroid eye disease, rosacea, ptosis, keratoconus, ocular pain syndrome, Steven-Johnson's syndrome, corneal epitheliopathies, corneal neuropathies (including LASIK induced corneal neuropathies), corneal dystrophies (including recurrent corneal dystrophies), epithelial basement membrane dystrophy, corneal erosions or abrasions (including recurrent corneal erosions or abrasions), ocular surface diseases, blepharitis, graft vs host disease, meibomitis, glaucoma, conjunctivochalasis, keratopathis (including herpetic keratopathy, filamentary keratopathy, band or bullous keratopathy, exposure keratopathy), keratitis (including herpes simplex virus keratitis), iritis, episclentis, corneal surgery, multiple sclerosis, trichiasis, pterygium, neuralgia, xerophthalmia, or patients recovering from neurotrophic keratitis. In some embodiments, the subject suffers from ocular pain persisting for at least three months after photorefractive keratectomy (PRK) surgery or laser-assisted in situ keratomileusis (LASIK) surgery.

In certain embodiments, methods provided herein is for treating, or reducing, ocular surface pain, such as acute ocular surface pain.

In certain embodiments, methods provided herein is for treating, or reducing, ocular surface pain, such as chronic ocular surface pain (COSP). In particular aspects, COSP is characterized as persistent ocular surface pain (e.g., persistent severe ocular surface pain) that can distract from, or can interfere with, regular daily activities. In specific aspects, COSP can result in poor quality of life, and can persist for at least 1 month, at least 2 months, at least 3 months, at least 4 months, at least 5 months, or at least 6 months. In some aspects, COSP can persist for at least about 2 months or at least about 3 months. In other aspects, COSP can persist for at least 3 months or at least 4 months. In particular aspects, subject with COSP remain symptomatic despite adherence to other therapies indicated for their underlying disease (e.g., an ocular surface disorder such as dry eye disease or Sjogren's Syndrome).

In some embodiments, the subject to be treated suffers from ocular neuropathic pain (ONP). ONP is a spectrum of disorders of ocular pain that may be caused by damage or disease affecting the nerves, e.g., corneal nerves. Symptoms of ONP may include one or more of eye pain, sensitivity to light, hyperalgesia or dysesthesia (abnormal sensations) such as a sensation of dryness, stinging, or foreign body, pain from normally non-painful stimuli (allodynia). Gabapentin and other neuropathic pain medications may be used to blunt sensory nerve stimulation or the perception of nerve stimulation.

In some embodiments, the subject to be treated suffers from exposure keratopathy. EK is damage to the cornea that occurs primarily from prolonged exposure of the ocular surface to the outside environment. EK can lead to ulceration, microbial keratitis, and permanent vision loss from scarring. Patients at risk for EK include those who suffer from conditions that interfere with the ability to protect the cornea; either by incomplete eyelid closure (e.g., lagophthalmos, proptosis, lid malposition), inadequate blink reflex, inadequate blink rate (for example, caused by a neurologic disease, e.g., Parkinson disease, a neuromuscular disease) and/or decreased protective lubrication of the cornea. Symptoms of EK include foreign body sensation, burning, increased tearing, and intermittent blurry vision (from an unstable tear film), pain and photophobia. Standard treatments include the use of frequent artificial tears with nightly lubricating ointment, punctal plugs.

In some embodiments, the subject to be treated suffers from keratoconjunctivitis. Keratoconjuctivitis is an inflammatory process that involves both the conjunctiva and the cornea. Superficial inflammation of the cornea (keratitis) occurs commonly in association with viral and bacterial conjunctivitis, for example in adults. The following types of keratoconjuctivitis are distinguished based on the potential cause of inflammation:

-   -   Keratoconjunctivitis sicca is cause by the inflammation due to         dryness;     -   Vernal keratoconjunctivitis (VKC) occurres seasonally,         considered to be due to allergens;     -   Atopic keratoconjunctivitis is one manifestation of atopy;     -   Epidemic keratoconjunctivitis or adenoviral keratoconjunctivitis         is caused by an adenovirus infection;     -   Infectious bovine keratoconjunctivitis (IBK) is a disease         affecting cattle caused by the bacteria Moraxella bovis;     -   Pink eye in sheep and goat is mostly caused by Chlamydophila         pecorum;     -   Superior limbic keratoconjunctivitis is thought to be caused by         mechanical trauma;     -   Keratoconjunctivitis photoelectrica (arc eye) means inflammation         caused by photoelectric UV light.

In some embodiments, the subject to be treated suffers from dry eye. The term “dry eye” as used herein, refers to inadequate tear production and/or abnormal tear composition. Dry eye syndrome disease (DEDS), also known as dry eye syndrome, keratoconjunctivitis sicca or keratitis sicca, or tear dysfunction syndrome, or burning eye syndrome results from deficiency of any of the tear film layers. Dry eye is a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance, and tear¬film instability with potential damage to the ocular surfaceocular surface characterized by loss of homeostasis of the tear film, and accompanied by ocular symptoms, in which tear film instability and hyperosmolarity, ocular surface inflammatoin and damage, and neuro-sensory abnormalities play etiological roles (Craig J P, et al., The Ocular Surface 2017; 15:276-83). It may be accompanied by increased osmolarity of the tear film and inflammation of the ocular surface. Dry eye disorder may range from mild to moderate to severe forms. Symptoms of dry eye syndrome disease include gritty, foreign body sensations, burning, photophobia, and decreased visual acuity, tearing, stinging, itching, sandy or gritty feeling, discharge, frequent blinking, mattering or caking of the eyelashes (usually worse upon waking), redness, blurry or fluctuating vision (made worse when reading, computer, watching television, driving, or playing video games), light-sensitivity, eye pain and/or headache, heavy eye lids, eye fatigue. Causes of dry eye disease include, but are not limited to, the following: idiopathic, congenital alacrima, xerophthalmia, lacrimal gland ablation, and sensory denervation; collagen vascular diseases, including rheumatoid arthritis, Wegener's granulomatosis, and systemic lupus erythematosus; Sjögren's Syndrome and autoimmune diseases associated with Sjögren's syndrome; abnormalities of the lipid tear layer caused by blepharitis or rosacea; abnormalities of the mucin tear layer caused by vitamin A deficiency; trachoma, diphtheric keratoconjunctivitis; mucocutaneous disorders; aging; menopause; and diabetes. Dry eye signs and/or symptoms as defined herein may also be provoked by other circumstances, including but not limited to the following: prolonged visual tasking; working on a computer; being in a dry environment; warm or cold wind or air flow; seasonal changes; ocular irritation; contact lenses, LASIK and other refractive surgeries; fatigue; and medications such as isotretinoin, sedatives, diuretics, tricyclic antidepressants, antihypertensives, oral contraceptives, antihistamines, nasal decongestants, beta-blockers, phenothiazines, atropine, and pain relieving opiates such as morphine.

Diagnostic testing for dry eye includes evaluation of cornea sensation (corneal hyperesthesia and/or reduced sensation may be present in severe and chronic dry eye disease) using, for example, a cotton tip applicator or more precisely with a Cochet-Bonnet esthesiometer; measuring tear break up time using, for example, a fluorescein-impregnated strip wet with non-preserved saline solution or more objective computerized methods without the need for fluorescein instillation; performing oculr surface staining, e.g., fluorescein sodium, rose bengal, lissamine green; performing Schirmer test (relatively insensitive for patients with mild dry eye), testing delayed tear clearance; tear meniscus height; measuring level of MMP-9 (MMP-9 has been shown to be elevated in the tears of patient with dry eye disease, and levels correlate with examination findings in patients with moderate to severe dry eye); measuring tear osmolarity and tear film interferometry; performing Sjo test (detection of SS-A (anti-Ro) and SS-B (anti-La) autoantibodies in serum, salivary gland protein 1 (SP-1), carbonic anhydrase 6 (CA6), and parotid secretory protein (PSP). SP-1, CA6, and PSP).

Artificial tears, lubricating ointments, corticosteroids (e.g., loteprednol 0.5% eyedrops four times a day) are used as an initial treatment. Prescription medicines include cyclosporine, lifitegrast, diquafosol, rebamepide, corticosteroids (e.g., loteprednol 0.5% eyedrops four times a day).

The term “tear film dysfunction” refers to a state when the tear film breaks down in different places on the cornea and conjunctiva, leading not only to symptoms of irritation, but also to unstable and intermittently changing vision. For example, dry eye syndrome disease is characterized by tear film dysfunction. The symptoms of tear film dysfunction include tearing, burning, stinging, itching, sandy or gritty feeling, scratchy or foreign-body sensation, discharge, frequent blinking, mattering or caking of the eyelashes (usually worse upon waking), redness, blurry or fluctuating vision (made worse when reading, computer, watching television, driving, or playing video games), light-sensitivity, eye pain and/or headache, heavy eye lids, eye fatigue.

Adenoviral keratoconjunctivitis, also known as Keratoconjunctivitis epidemica is a common and highly contagious viral infection of the eye. The clinical course of Adenoviral keratoconjunctivitis is divided into an acute phase with conjunctival inflammation of varying intensity with or without corneal involvement and a chronic phase with corneal opacities.

Vernal keratoconjunctivitis (VKC) is an atopic condition of the external ocular surface characterized by symptoms consisting of severe itching, photophobia, foreign body sensation, mucous discharge (often described as “ropy”), blepharospasm, and blurring of vision (Buckley, R. J., Int Ophthalmol Clin, 1988 28(4): p. 303-8; Kumar, S., Acta Ophthalmologica, 2009. 87(2): p. 133-147). It is typically bilateral but may be asymmetric in nature. It characteristically affects young males in hot dry climates in a seasonal manner; in 23% of patients may have a perennial form (Kumar, S., Acta Ophthalmologica, 2009. 87(2): p. 133-147; Bonini, S., et al., Ophthalmology, 2000. 107(6): p. 1157-63).

The signs of VKC can be divided into conjunctival, limbal and corneal signs:

-   -   Conjunctival signs include diffuse conjunctival injection and         upper tarsal giant papillae that are discrete >1 mm in diameter;     -   Limbal signs include thickening and opacification of the limbal         conjunctiva as well as gelatinous appearing and sometime         confluent limbal papillae. Peri-limbal Horner-Trantas dots are         focal white limbal dots consisting of degenerated epithelial         cells and eosinophils (Buckley, R. J., Int Ophthalmol         Clin, 1988. 28(4): p. 303-8);     -   Corneal signs vary according to the severity of the disease         process and include macro-erosions, cornal ulcers and scars         (Buckley, R. J., Int Ophthalmol Clin, 1988. 28(4): p. 303-8).

Active VKC patients (defined as moderate to severe ocular discomfort including photophobia, papillae on the upper tarsal conjunctiva, or limbal Horner-Trantas dots clearly recognizable at the time of the examination) showed significantly increased symptoms and signs of ocular surface disease. Inactive VKC patients (defined as no symptoms or mild discomfort, and absence of corneal abnormalities at the time of the examination) showed increased photophobia, conjunctival lissamine green staining and Schirmer test values, and reduced fluorescein break-up time (BUT) and corneal sensitivity. This syndrome seems to affect the ocular surface in all phases (active and quiescent), determining abnormalities in tear film stability, epithelial cells integrity, and corneal nerves function (Villani E. et al., Medicine (Baltimore). 2015 October; 94(42): e1648).

The following factors are thought to play a role in VKC: IgE mediate reaction via mast cell release; activated eosinophils, mononuclear cells and neutrophils as well as the CD4 T-helper-2 driven type IV hypersensitivity with immunomodulators such as IL-4, IL-5, and bFGF (Buckley, R. J., Int Ophthalmol Clin, 1988. 28(4): p. 303-8; Kumar, S., Acta Ophthalmologica, 2009. 87(2): p. 133-147; La Rosa, M., et al., Ital J Pediatr, 2013. 39: p. 18).

Treatment consists of cool compresses and lid scrubs, saline eyedrops, which may help to relieve symptoms, along with topical antihistamines, nonsteroidal anti-inflammatory drugs or corticosteroids, e.g., low-absorptions corticosteroids (fluoromethelone, loteprednol, remexolone, etc.), opical mast cell stabilizers (cromolyn sodium, nedocromil sodium, and lodoxamide), topical cyclosporin-A, or tacrolimus. See e.g., Oray, M. and E. Toker, Cornea, 2013. 32(8): p. 1149-54: Vichyanond, P. and P. Kosrirukvongs, Curr Allergy Asthma Rep, 2013. 13(3): p. 308-14; Barot, R K et al., J Clin Diagn Res. 2016 June; 10(6):NC05-9; Wan Q et al., Ophthalmic Res. 2018; 59(3):126-134.

Atopic keratoconjunctivitis (AKC) typically has an older age of onset in the 2nd to 5th decade, as opposed to onset prior to age 10 with VKC. Conjunctival involvement is classically on the upper tarsus in VKC and on the lower tarsus in AKC. AKC is typically more chronic in nature and more commonly results in scarring of the cornea and conjunctival cicatrization.

Sjogren's Syndrome (Sjogren's syndrome associated with dry eye) is a chronic inflammatory disorder characterized by exocrine gland dysfunction including the salivary and lacrimal glands that in many cases results in a severe dry eye. Primary symptoms are dry eyes (keratitis sicca or keratoconjunctivitis sicca) and dry mouth (xerostomia). Severe dry eyes can cause corneal pain, corneal scarring, ulceration, infection, and even perforation. The differential diagnosis includes conditions such as adult blepharitis, dry eye disease, and juvenile idiopathic arthritis uveitis, as well keratopathies, e.g., superficial punctate, filamentary, neurotrophic, exposure). Treatment of Sjogren's syndrome is aimed at maintaining the integrity of the tear film through preservation, augmentation, and/or replacement of the deficient tear secretion. Treatment of Sjogren's syndrome thus includes artificial tears and lubricating ointments; autologous serum eyedrops; oral omega-6 essential fatty acids; fluid-ventilated, gas permeable scleral lenses; topical corticosteroids; punctal occlusion to decrease tear drainage; a small lateral tarsorrhaphy; humidification of the environment; hydrophilic bandage lenses; bromhexine and 3-isobutyl 1-methylxanthine (IBMX) (augmentation of tear production/secretion); agents to stimulate muscarinic receptors (pilocarpine and cevimeline); immunosuppressive agents, e.g., methotrexate, antimalarials, cyclophosphamide, leflunomide, or tumor necrosis factor (TNF), e.g., infliximab, a monoclonal antibody to TNF-alpha; Cyclosporin A; the bandage contact lens.

Steven-Johnson's syndrome (SJS) is a dermatologic emergency or a type of severe skin reaction characterized by the presence of epidermal and mucosal bullous lesions involving less than 10% of the total body surface area. Early symptoms of SJS include fever and flu-like symptoms, which may precede or occur concurrently with the development of a macular rash involving the trunk and face. As the disease progresses, the macular rash coalesces, the involved areas develop bullae, and the epidermal layer eventually sloughs off. During the acute phase of SJS-TEN, 80% of patients will have ocular involvement.

The constellation of high fever (>102.2), malaise, arthralgia, a macular rash involving the trunk, neck and face, and recent history of new medication exposure or recently increased dosage of an existing medication are indicators used for diagnosis of SJS. A skin biopsy of an effected area can be performed for a confirmation of the diagnosis. Granulysin can be used as a marker for the diagnosis of SJS. The concentration of granulysin within bullous fluid correlates with the severity of the acute phase of SJS (Chung W H, et al. Nat Med. 2008; 14(12):1343-50).

Ocular manifestations in SJS include conjunctivitis, subconjunctival hemorrhage, subconjunctival scarring, conjunctival membranes, conjunctival ulceration, superficial punctate epithelial erosions, epithelial defects, lid margin ulceration, lid margin keratinization, symblepharon, ankyloblepharon, trichiasis, anterior blepharitis, punctal auto-occlusion, meibomian gland disease, corneal opacification, dry eye, districhiasis, limbal stem cell failure, corneal vascularization. Eye treatment in SJS consists of saline eyedrops, preservative-free artificial tears and ointments to provide adequate lubrication and reduce epithelial injury. Patients with any corneal or conjunctival epithelial defects are treated with prophylactic topical antibiotics, preferably a fourth generation fluoroquinolone. Patients having mild or moderate ocular involvement (less than one-third lid margin involvement, conjunctival defects less than 1 cm at greatest diameter, and no corneal epithelial defects) are typically treated with topical moxifloxacin 0.5% four times a day, cyclosporine 0.05% twice daily, and topical steroids (prednisolone acetate 1% four to eight times a day or dexamethasone 0.1% twice daily). Patients having severe or extremely severe ocular involvement (greater than one-third lid margin involvement, conjunctival defects greater than 1 cm, and corneal epithelial defects) undergo an amniotic membrane (AM) grafting in addition to the treatments listed above.

In some embodiments, the subject to be treated suffers from corneal epithelipathy. Corneal epitheliopathy is a disease involving corneal epithelium, e.g., manifested in altered corneal epithelial barrier function.

In some embodiments, the subject to be treated suffers from corneal neuropathy or corneal neuralgia. Corneal neuropathy or corneal neuralgia is a disorder associated with corneal pain caused by the damaged nerve fibers in the cornea, the sensory fibers. One of the examples of corneal neuropathy is a LASIK induced corneal neuropathy. Corneal neuropathy generally could be identified and diagnosed through dry eye investigations. Though the causes and risk factors are unclear yet, patients with dry eye-like symptoms, increased corneal sensitivity and changes of corneal nerve morphology, but no signs of dryness may suffer from corneal neuropathy.

In some embodiments, the subject to be treated suffers from ocular surface disease or disorder. The term “ocular surface diseases” or “ocular surface disorders” encompasses disease entities as well as related symptoms that result from a variety of abnormalities, including abnormal lid anatomy or function, abnormal or altered tear production or composition, and related subclinical signs. Many diseases can cause ocular surface disorders. Patients with ccular surface disorders may exhibit clinical signs common to several diseases, and include chronic punctate keratopathy, filamentary keratopathy, recurrent corneal erosion, bacterial conjunctivitis, culture-negative conjunctivitis, cicatrising (scarring) conjunctivitis, persistent epithelial defect, infectious keratitis, corneal melt and ocular surface failure. The most common ocular surface disorders stem from tear-film abnormalities and/or lid-gland dysfuntion (“blepharitis”).

In some embodiments, the subject to be treated suffers from neurotrophic keratitis or neurotrophic keratopathy. Neurotrophic keratitis or neurootrophic keratopathy (NK) is a corneal degenerative disease characterized by a reduction or absence of corneal sensitivity. In NK, corneal innervation by trigeminal nerve is impaired. Since corneal sensory innervation is impaired in NK, patients do not commonly complain of ocular surface symptoms. However, blurred vision can be reported due to irregular epithelium or epithelial defects (PED), scarring, or edema. NK is usually graded in three different stages in accordance to the “Mackie classification”. Stage II NK is defined by a recurrent or persistent epithelial defects, most commonly in the superior half of the cornea. One of the treatments that may be used in Stage II NK includes topical Nerve Growth Factor. Patients typically experience pain during treatment with NGF due to reforming of the nerves.

In some embodiments, the subject to be treated suffers from blepharitis. Blepharitis is an inflammatory condition of the eyelid margin, which can lead to permanent alterations in the eyelid margin or vision loss from superficial keratopathy, corneal neovascularization, and ulceration. According to anatomic location, blepharitis can be divided into anterior and posterior. Anterior blepharitis affects the eyelid skin, base of the eyelashes, and the eyelash follicles and includes the traditional classifications of staphylococcal and seborrheic blepharitis. Posterior blepharitis affects the meibomian glands and gland orifices, the primary cause being meibomian gland dysfunction. Symptoms of chronic blepharitis may include redness, burning sensation, irritation, tearing, eyelid crusting and sticking, and visual problems such as photophobia and blurred vision. Long-term management of symptoms may include daily eyelid cleansing routines and the use of therapeutic agents that reduce infection and inflammation. Treatment includes topical or systemic antibiotics e.g., bacitracin or erythromycin; oral antibiotics, e.g., tetracyclines (tetracycline, doxycycline, minocycline) or macrolides (erythromycin, azithromycin); topical steroids, e.g., corticosteroid, e.g., loteprednol etabonate, fluorometholone; topical combinations of an antibiotic and corticosteroid such as tobramycin/dexamethasone or tobramycin/loteprednol; topical cyclosporine 0.05%.

In some embodiments, the subject to be treated suffers from Meibomian gland dysfunction. The meibomian gland is a holocrine type of exocrine gland, at the rim of the eyelid inside the tarsal plate, responsible for the supply of meibum, an oily substance that prevents evaporation of the eye's tear film. Meibomian gland dysfunction (MGD), also known as meibomitis, posterior blepharitis or inflammation of the meibomian glands, is a chronic, diffuse abnormality of the meibomian glands, commonly characterized by terminal duct obstruction and/or qualitative/quantitative changes in the glandular secretion (Nelson J D, et al., Invest Ophthalmol Vis Sci 2011; 52:1930-7). It may result in alteration of the tear film, symptoms of eye irritation, clinically apparent inflammation, and ocular surface disease. MGD often causes dry eye, and may contribute to blepharitis. In some cases topical steroids and topical/oral antibiotics are also prescribed reduce inflammation. Intense pulsed light (IPL) treatments or other mechanical treatments that apply heat and pressure to express the glands (eg, LipiFlow) have also been shown to reduce inflammation and improve the gland function in patients.

In some embodiments, the subject to be treated suffers from graft-versus-host disease. Graft-versus-host disease (GVHD) is an inflammatory disease that is unique to allogeneic transplantation. It is an attack by transplanted leukocytes against the recipient's tissues that can occur even if the donor and recipient are HLA-identical. Acute graft-versus-host disease typically occurs in the first 3 months after transplantation and may involve the skin, intestine, or the liver. Corticosteroids such as prednisone are a standard treatment. Chronic graft-versus-host disease may also develop after allogeneic transplant and is the major source of late complications. In addition to inflammation, chronic graft-versus-host disease may lead to the development of fibrosis, or scar tissue, similar to scleroderma or other autoimmune diseases and may cause functional disability, and the need for prolonged immunosuppressive therapy.

In some embodiments, the subject to be treated suffers from ocular graft versus host disease. GVHD occurs in patients who have undergone allogenic hematological stem cell transplantation. It can occur in patients who have acute or chronic GVHD, though it is more common in patients with the chronic form. Approximately 40-90% of patients with chronic GVHD will develop ocular symptoms. Ocular manifestations can include moderate to severe keratoconjuncitvitis sicca, bilateral marginal keratitis, anterior uveitis, corneal ulceration or neovascularization. Treatment includes topical lubricants including preservative free artificial tears, autologous serum tears and other topical and systemic immunosuppressive treatments; systemic steroids; topical cyclosporine 0.5%.

EXAMPLES

The following examples are included to demonstrate nonlimiting embodiments of the present invention.

Example 1. First in Human Study of Compound I for Assessment of Safety and Pharmacokinetics

This example describes a first-in-human study of compound I conducted in healthy volunteers. A total of 54 subjects were administered to study medication. Part 1 of the first in human study administered single ascending doses of 0.15%, 1.5%, 2.5% w/v (1 drop) of compound I in an eye drop.

Part 2 tested multiple ascending doses (MAD) of compound I, administering (i) 1 drop of 0.15%, 1.5%, 2.5%, 4 times daily (every 6 hours) for 7 days or (ii) 1 drop of 2.5%, 8 times daily (every 3 hours) for 7 days (supra-therapeutic dose) as eye drops.

Part 3 was an esthesiometry assessment to evaluate the anesthetic properties of compound I. Part 3 of the study had four arms, with compound I, vehicle, tetracaine (0.5% ophthalmic solution, used as a positive control) and diclofenac sodium (0.1% ophthalmic solution, used as the active NSAID comparator). Ocular anesthetic was selected because of its established anesthetic effect; however it is not the standard of care due to its negative effect on wound healing. NSAID is the current standard of care for corneal pain after PRK with minimal anesthetic but significant pain control properties. Vehicle eye drops were used as a negative control to enable better determination of the potential anesthetic effect. Twelve healthy subjects, who met the eligibility criteria, were randomized to receive a single eye drop of 4 study treatments, each during 1 of 4 different study days (Days 1, 4, 7 and 10). Each subject was randomized to receive the study treatment according to one of the following four sequences:

-   -   Sequence 1: Anesthetic, NSAID, compound I 2.5%, Vehicle     -   Sequence 2: NSAID, Vehicle, Anesthetic, compound I 2.5%     -   Sequence 3: Vehicle, compound I 2.5%, NSAID, Anesthetic     -   Sequence 4: compound I 2.5%, Anesthetic, Vehicle, NSAID

Safety assessments: Safety assessments consisted of collecting all adverse events (AEs), serious adverse events (SAEs), including systemic and ocular adverse events, along with their severity and relationship to study drug. Systemic safety assessments included regular monitoring of hematology, blood chemistry and urinalysis performed at study center and regular assessments of physical examination, vital signs (systolic and diastolic blood pressure, pulse rate, and body temperature), ECG, pregnancy and assessments of fertility and hand immersion test at 49° C. during MAD part. Ocular safety assessments included early treatment diabetic retinopathy study (ETDRS) visual acuity, intraocular pressure, slit-lamp biomicroscopy, corneal staining and dilated fundus exam.

Subjects were selected based on the following inclusion and exclusion criteria.

Inclusion Criteria:

-   -   Written informed consent was obtained before any assessment was         performed.     -   Healthy male and female subjects aged 18 to 50 years         (inclusive), and in good health as determined by past medical         history, physical examination, vital signs, ECG, and laboratory         tests at Screening.     -   At Screening, and Baseline, vital signs (systolic and diastolic         blood pressure (BP) and pulse rate) were assessed in the sitting         position after the subject had rested for at least 3 minutes and         again after 3 minutes in the standing position. Sitting vital         signs were required to be within the normal range the following         ranges:     -   oral body temperature between 35.0-37.5° C.     -   systolic blood pressure (SBP), 90-150 mmHg     -   diastolic blood pressure (DBP), 50-90 mmHg     -   pulse rate, 40-100 bpm     -   Subjects were required to weigh at least 50 kg to participate in         the study, with a body mass index (BMI) within the range of         18-29 kg/m2. BMI=Body weight (kg)/[Height (m)]²     -   Subjects who were able to communicate well with the         Investigator, to understand and comply with the requirements of         the study.     -   For Part 3, subjects Baseline levels of eye sensitivity were to         be in the range of 50 to 60 mm (inclusive) as measured by the         Cochet-Bonnet esthesiometer.

Exclusion Criteria:

-   -   Women of child-bearing potential, defined as all women         physiologically capable of becoming pregnant, unless they were         using effective methods of contraception during dosing of study         treatment.     -   Subjects, who demonstrated any medical condition (systemic or         ophthalmic) that was, in the opinion of the Investigator, and         based on the content of the Investigator brochure, preclude the         safe administration of test article or safe participation in         this study.     -   Part 3 (esthesiometry): subjects who were using contact lenses         at the time of the study or had used in the past 3 years were         excluded to minimize variability in corneal sensitivity because         of contact lens use.     -   History of any ocular surgery or laser within the past 6 months         prior to Screening. History of any chronic eye disease other         than refractive error, incipient cataract, strabismic amblyopia,         or anisometropic amblyopia. Subjects with a history of acute eye         disease (such as infection, corneal abrasion or allergy) within         the past 6 months from Screening were eligible if the disease         was not active.     -   Any currently active ocular condition that required use of         topical eye drops.     -   Subjects using continuous positive airway pressure or other         sleep apnea devices.

Safety Results from the First in Human Study

Based on results from Parts 1, 2, and 3, the Maximum Tolerated Dose (MTD) was identified as the maximum feasible concentration of 2.5%, 8 times daily for 7 days. No dose limiting adverse events were identified at this dose level. All adverse events of suspected causality to compound I were of mild severity, except for moderate severity eye irritation that lead to discontinuation of treatment in one patient of the 2.5% 4 times daily cohort. The most frequent ocular adverse events in the compound I treated patients were corneal staining, hyperemia and mild anterior chamber inflammation, in levels similar to placebo. A summary of the adverse events from the SAD study are shown in Table 1.

TABLE 1 Overall incidence of AEs - number of events and number of subjects (Part 1: SAD) (Safety analysis set) Compound I Compound I Compound I 0.15% 1.5% 2.5% Vehicle Total N = 6 N = 6 N = 6 N = 6 N = 24 nE, nS (%) nE, nS (%) nE, nS (%) nE, nS nE, nS (%) AEs, Subjects with AEs 3, 1 (16.7) 3, 2 (33.3) 0, 0 (0.0) 4, 3 (50.0) 10, 6 (25.0) AEs of Mild severity 3, 1 (16.7) 3, 2 (33.3) 0, 0 (0.0) 3, 2 (33.3) 9, 5 (20.8) AEs of Moderate severity 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) 1, 1 (16.7) 1, 1 (4.2) Study drug-related AEs 3, 1 (16.7) 3, 2 (33.3) 0, 0 (0.0) 3, 2 (33.3) 9, 5 (20.8) Serious AEs 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) AEs leading to 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) 1, 1 (16.7) 1, 1 (4.2) of study Study-drug related 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) 1, 1 (16.7) 1, 1 (4.2) AEs leading to discontinuation of study N = number of subjects enrolled and received the study drug nE = number of treatment emergent AE events in the category nS = number of subjects with at least one treatment emergent AE in the category Percent is based on the number of subjects

A summary of the adverse events from the SAD study are shown in Table 2.

TABLE 2 Overall incidence of AEs - number of events and number of subjects (Part 2: MAD) (Safety analysis set) Compound I Compound I Compound I Compound I 0.15% 1.5% 2.5% 2.5% 4 times daily 4 times daily 4 times daily 8 times daily Vehicle Total N = 6 N = 6 N = 6 N = 6 N = 8 N = 32 nE, nS (%) nE, nS (%) nE, nS (%) nE, nS (%) nE, nS nE, nS AEs, 6, 3 (50.0) 12, 5 (83.3) 4, 2 (33.3) 3, 2 (33.3) 13, 3 (37.5) 38, 15 (46.9) Subjects with AEs AEs of Mild 6, 3 (50.0) 11, 5 (83.3) 3, 2 (33.3) 3, 2 (33.3) 12, 3 (37.5) 35, 15 (46.9) severity AEs of 0, 0 (0.0) 1, 1 (16.7) 1, 1 (16.7) 0, 0 (0.0) 1, 1 (12.5) 3, 3 (9.4) Moderate Severity Study drug- 5, 2 (33.3) 9, 3 (50.0) 4, 2 (33.3) 2, 1 (16.7) 10, 3 (37.5) 30, 11 (34.4) related AEs Serious AEs 0, 0 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) 0, 0 (0.0) (0.0) AEs leading 0, 0 (0.0) 0, 0 (0.0) 1, 1 (16.7)^(a) 0, 0 (0.0) 0, 0 (0.0) 1, 1 (3.1) to discon- tinuation of Study Study-drug 0, 0 (0.0) 0, 0 (0.0) 1, 1 (16.7) 0, 0 (0.0) 0, 0 (0.0) 1, 1 (3.1) related AEs N = number of subjects enrolled and received the study drug nE = number of treatment emergent AE events in the category nS = number of subjects with at least one treatment emergent AE in the category Percent is based on the number of subjects ^(a)Subject treated with compound I 2.5% 4 times daily experienced eye discharge, ocular hyperemia (both of mild severity) and eye irritation (moderate severity) in the left eye on Day 6., leading to discontinuation of the administration of study drug.

For the hand immersion test, all subjects in the treatment cohorts withdrew their hand from water at 49° C. at a time interval between 0 to <50 secs. No subjects lasted longer than 22 secs and no meaningful change in immersion time was observed between compound I and vehicle-treated subjects. The results therefore indicate that compound I does not alter temperature sensitivity of the subjects.

Esthesiometry Study (Part 3)

The first-in-human study further evaluated potential anesthetic effect of topical ocular 2.5% compound I by esthesiometry testing, i.e. measurement of the filament length (cm) when the threshold of cornea touch is perceived.

An analysis of the results showed that tetracaine 0.5% had an anesthetic effect with approximately 10 minutes of duration of action (positive control). Both diclofenac 0.1% and vehicle had no anesthetic effect on the cornea, as expected based on known clinical experience with diclofenac. Compound I 2.50% showed no anesthetic effect at any time point after treatment.

For measures of corneal sensitivity, statistical and clinical significance were observed while comparing least squares means (Test vs Ref) for the following:

-   -   Tetracaine 0.5% (N=12) vs Vehicle (N=12) at 2.5 minutes, 10         minutes and 20 minutes post-dose;     -   Tetracaine 0.5% (N=12) vs Diclofenac 0.1% (N=12) at 2.5 minutes,         10 minutes and 20 minutes post-dose;     -   Compound I 2.5% (N=11) vs Tetracaine 0.5% (N=12) at 2.5 minutes         and 10 minutes post-dose

No difference was seen in corneal sensitivity between compound I 2.5% and vehicle, with all p-values greater than or equal to 0.395 at scheduled time points up to 30 minutes post-dose. This study demonstrated a lack of anesthetic effect of 2.5% compound I when compared to tetracaine 0.5% (drug with anesthetic effect as positive control) and vehicle (placebo).

Pharmacokinetic Summary from First in Human Study

After both single and multiple topical ocular suspension doses of compound I 0.15%, 1.5%, and 2.5%, plasma PK profile showed rapid absorption of compound I into systemic circulation and low concentration exposures achieved with moderate variability across subjects. Increase in dose from 0.15% to 2.5% resulted in less than dose-proportional increase in systemic exposure. Accumulation of compound I at steady-state was minor (˜1.7-fold) following administration of 0.15%, 1.5% or 2.5% suspension 4 times daily and also minor (˜1.3-fold) following 2.5% 8 times daily for 7 days.

Example 2. Clinical Study of Compound I for Treatment of Postoperative Pain

This example describes a clinical study of compound I (4-(7-hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile) in the treatment of postoperative ocular pain in patients undergoing photorefractive keratectomy (PRK) surgery.

Study Objectives

Primary objective Endpoints related to primary objective To evaluate pain control in Visual analog scale (VAS) pre-dose pain the immediate post-operative assessment at 6 hours post-operatively period. Average ocular pain VAS assessments from the first post-operative assessment up to the pre-dose 12 hour assessment Secondary objectives Endpoints related to secondary objectives To evaluate the efficacy of Incidence and amount of rescue oral compound I 2.5% eye drops analgesics needed in 6 hours, four times daily for 12 hours, 24 hours, 2 days, and reducing use of oral 3 days post-operatively after each analgesics following PRK surgery. PRK procedure To assess safety and Adverse events (AEs) and serious tolerability of compound I adverse events (SAEs) 2.5% eye drops four Visual acuity, intraocular pressure times daily (IOP), dilated fundus exam, ocular hyperemia Size of epithelial defect by slit lamp exam Blink rate, tear production Vital signs (blood pressure, pulse rate, and body temperature) To evaluate pain severity All VAS measurements during the post-operatively first 3 days after surgery To assess the systemic Plasma concentration of compound I exposure after ocular dosing of compound I 2.5% eye drops four times daily at various time points in PRK patients Exploratory objectives Endpoints related to exploratory objectives To explore wound healing Size of epithelial defect by anterior rate segment Optical coherence tomography (OCT) To explore effect on pain VAS scores before and after relief of compound I instillation of eye drop (three time versus Vehicle after points) instillation of eye drop To explore effect of Ocular Pain Assessment Survey (OPAS) compound I on ocular pain and quality of life compound I exposure in Residual compound I amount after the bandage contact treatment lens (BCL)

Study Design

The study was a proof of concept, double-masked, randomized, vehicle-controlled study of compound I administered as eye drops in addition to standard of care treatment in patients after PRK surgery. PRK surgery was performed as an outpatient procedure under topical anesthesia with removal of the corneal epithelium to expose the stroma for the laser ablation. Compound I dosing was as single eye drop of 2.5% (25 mg/ml, 0.925 mg/drop), administered four times daily (every six hours) in one eye from immediate post-op (time 0) to last dose at 72 hours.

Vehicle dosing was as a single drop, administered four times daily (every six hours) in one eye from immediate post-operative (time 0) to last dose at 72 hours.

The study consisted of 2 treatment periods using a crossover design. Patients underwent PRK surgery on 2 separate occasions (periods), one eye at a time. Patients were randomized to receive either compound 1 or vehicle following procedure 1 and the alternate following procedure 2.

Forty patients were randomized in a 1:1 ratio to two sequences: compound I during period 1, followed by vehicle in period 2, or vehicle during period 1 followed by compound I during period 2. Each patient was administered one drop four times daily for 72 hours following PRK surgery on their study eye (Day 1, Periods 1 and 2). The initial study eye was the non-dominant eye as established at screening and in agreement of the patient and the investigator. The patients returned for follow-up visits on Days 2, 3, 4 and 8 of Period 1 after surgery in the first eye, with optional daily visits to follow the patient until wound healing was complete. The second eye surgery was not performed if any complications were noticed.

The patients underwent PRK surgery on their second study eye (dominant eye) on Period 2, Day 1. The PRK surgery was performed after the epithelial defect of the first eye was resolved and at the discretion of the Investigator. Following the PRK surgery, the patients received the opposing treatment four times daily for 72 hours. Patients returned daily for the first 3 postoperative days (Period 2, Days 2-4) and at one week after the second surgery (Period 2, Day 8), with optional daily visits to follow the patient until wound healing was complete. An end of study (EOS) visit took place 30 days after the second eye surgery (or after final dose of investigational product when the patient ended treatment early in Period 1).

All patients received standard of care treatment during periods 1 and 2 of the study, including application of a bandage contact lens (Air Optix® Night and Day® Aqua or equivalent) following the PRK procedure and before receiving study drops for pain. A course of topical ocular antibiotic (Moxifloxacin or equivalent 1 eye drop four times daily) was started after application of first dose of study drops and was continued for 4-7 days. Prednisolone acetate ophthalmic one eye drop four times daily was administered for one week after PRK, followed by taper. Preservative-free unit-dose artificial tears were used as needed. The first dose of study drops after each PRK procedure was administered by site staff. Subsequent doses were self-administered. A gap of 5 minutes was allowed between eye drop administrations in sequence. To summarize, patients underwent PRK procedure, bandage lens was placed on the cornea, compound I or Vehicle was administered; after approximately 5 minutes antibiotic was administered, and after another 5 minutes, prednisolone was administered.

Rescue medication consisted of oral analgesic (acetaminophen 300 mg+codeine 30 mg) as needed up to a total of 10 tabs/day or 1-2 tabs every 4 hours.

Additional Study Treatment

All patients received standard of care ancillary treatment following PRK surgery, including:

-   -   Bandage contact lens (Air Optix® Night and Day® Aqua or         equivalent)     -   A course of topical ocular antibiotic (Moxifloxacin or         equivalent 1 eye drop four times daily) was started right after         PRK surgery, and after application of first dose of study eye         drop and continued for 4-7 days, per managing physician.     -   Prednisolone acetate ophthalmic: one eye drop four times daily         was started immediately following PRK surgery and after         instillation of antibiotic eye drop and was administered for 1         week after PRK, followed by taper per local procedures.     -   Preservative-free unit-dose artificial tears were used as         needed. Artificial tears were not allowed to be chilled for         analgesic effect.

The drops were administered in sequence, with a gap of at least 5 minutes between eye drop administrations.

Inclusion Criteria

Population eligible for inclusion in this study had to fulfill all of the following criteria:

-   -   Male and female patients aged 18 to 75 years eligible for         bilateral PRK surgery.     -   Normal eye exam except for refractive error at Baseline.     -   Planned myopia correction was required not to exceed −4.00         Diopters (sphere) and 3.00 diopters of astigmatism, with         spherical equivalent not higher than −4.50, confirmed by         manifest refraction at Baseline. Monovision treatment (such as         correction for far distance in one eye and for intermediate         distance in the fellow eye) was allowed.     -   Written informed consent was obtained before any assessment was         performed.

Exclusion Criteria

-   -   Monocular patient (including amblyopia) or best corrected visual         acuity (BCVA) score worse than 20/80 (Snellen) or 55 letters         [early treatment diabetic retinopathy study (EDTRS)] at         Baseline.     -   Any systemic or ocular disease that affected wound healing (such         as severe rheumatoid arthritis or diabetes or history of keloid         formation) or a history of ocular trauma, uveitis, infection, or         inflammation in the 6 months prior to Baseline. Especially for         diabetes: Patients with severe diabetes, uncontrolled diabetes,         diabetic keratopathy, diabetic retinopathy, diabetic macular         edema, diabetic nephropathy, diabetic foot ulcers or other         systemic complications of diabetes were excluded. Patients with         mild, well-controlled diabetes with no evidence of ocular or         systemic complications of diabetes were included.     -   Patients with active inflammatory or infectious ocular         conditions, severe or progressive retinal disease, and use of         topical or systemic steroids, or use of Coumadin or similar         drugs within the last 6 months prior to Baseline.     -   Patients with any corneal dystrophy (epithelial, stromal or         endothelial) or any cornea disease (including significant         scarring (at the discretion of the Investigator), ocular herpes         or pterygium).     -   Previous refractive or corneal surgery (such as LASIK, PRK,         radial keratotomy, pterygium removal, corneal transplantation).     -   History of allergic or hypersensitivity reaction or significant         AEs to any of the drugs used in this study including tetracaine         or similar topical ocular anesthetic, NSAIDs and aspirin, oral         analgesic (including acetaminophen and codeine), antibiotics,         steroids and inability to tolerate or wear bandage contact lens     -   Concurrent therapy or history of chronic therapy or abuse of         systemic or ocular NSAIDs, analgesics, pain medication         (including gabapentin or pregabalin and similar), opiates or         cannabis.     -   Patients who used any topical eye medication except for         lubricating eye drops within two weeks prior to surgery in the         study eye were excluded. Patients meeting any of the following         were excluded:         -   Usage of topical NSAIDs during 30 days before Baseline, OR         -   Systematic/chronic usage of systemic NSAIDS within 30 days             prior to Baseline, OR         -   Occasional usage of systemic NSAIDS within 3 days prior to             Baseline, OR         -   Usage of ocular cyclosporine (or similar medication) within             the 3 months prior to surgery.     -   Patients with body weight <50 kg, or who do not have a body mass         index (BMI) within the range of 18-35 kg/m². BMI=Body weight         (kg)/[Height (m)]²     -   Pregnant or nursing (lactating) women. Women of child-bearing         potential, defined as all women physiologically capable of         becoming pregnant, unless they are using basic methods of         contraception during dosing of investigational drug.

No additional exclusions were applied by the Investigator, in order that the study population was the representative of all eligible patients.

Study Population

The study population was comprised of male and female patients eligible for PRK surgery between 18 and 75 years old (inclusive). A total of 40 patients were planned. A total of 44 patients were screened and of them 40 patients were enrolled in the study and randomized.

Patient selection was established based on a review of all eligibility criteria at Screening and Baseline. A relevant record (e.g. checklist) of the eligibility criteria was stored with the source documentation at the study site. Deviation from any entry criterion excluded a patient from enrollment into the study.

Patient demographics are provided in Table 3.

TABLE 3 Patient demographics by treatment sequence (Safety analysis set) Vehicle/ compound I compound I 2.5%/ 2.5% Vehicle Total N = 20 N = 20 N = 40 Age (years) Mean (SD) 34.4 (10.77) 33.7 (8.94) 34.0 (9.78) Median 33.5 32.0 33.0 Range 20-54 23-56 20-56 Sex - n(%) Male 11 (55%) 10 (50%) 21 (53%) Female 9 (45%) 10 (50%) 19 (48%) Race - n(%) White 18 (90%) 17 (85%) 35 (88%) Asian 2 (10%) 1 (5%) 3 (8%) Black Or 0  1 (5%) 1 (3%) African American Multiple 0  1 (5%) 1 (3%) Ethnicity - n(%) Not Hispanic 19 (95%) 18 (90%) 37 (93%) Or Latino Hispanic Or 1 (5%) 2 (10%) 3 (8%) Latino Weight (kg) Mean (SD) 84.1 (14.86) 78.8 (14.07) 81.5 (14.53) Median 84.7 76.1 79.2 Range  60-119  57-107  57-119 Height (cm) Mean (SD) 170.4 (7.40) 173.2 (6.96) 171.8 (7.23) Median 171.3  174.1  172.7  Range 155-184 161-185 155-185 BMI (kg/m²) Mean (SD) 28.9 (3.98) 26.2 (3.73) 27.5 (4.04) Median 29.7 26.0 27.5 Range 21-35 21-35 21-35 BMI = body mass index

Treatment Arms

Patients were assigned to one of the following 2 treatment sequences in a ratio of 1:1 lasting 3 days per period.

Sequence Period 1 Period 2 1 Compound I 2.5% Vehicle control 4 times daily (every 6 hours) 4 times daily (every 6 hours) for 72 hours (inclusive) for 72 hours (inclusive) 2 Vehicle control Compound I 2.5% 4 times daily (every 6 hours) 4 times daily (every 6 hours) for 72 hours (inclusive) for 72 hours (inclusive)

Compound I was administered to the patient as ocular drops. Drops were administered at the study site by the study personnel during the day of PRK surgery. During the daily follow-up postoperative visits, when the patient was at the site during the expected time for eye drop administration, the study personnel was required to administer the eye drops. The remainder of drops were home administered by the patient, or when the patient was present at the study site for a visit (e.g., at 24, 48 and 72 hours post-surgery).

Visual Analog Scale

Patient subjective experience of pain was recorded using VAS, a numeric assessment of pain between 0 and 100, with 0 representing no pain, and 100 representing worst imaginable pain. Previous studies of pain in PRK showed that the most intense pain was experienced within the first 12 hours after surgery with the peak around 4-6 hours after surgery (Sher et al., Refract Corneal Surg. November-December; 9(6):425-36 (1993)), and these were the time points selected for primary endpoint analysis. Since it was important clinically to both decrease the maximum pain as well as the overall pain that the patient experiences during the immediate postoperative period, the two periods of 6 hours and up to 12 hours postoperatively, were evaluated as primary endpoints. All evaluable VAS data was collected using an ePRO, which was an electronic device (cell phone with software application), on which patients marked their pain levels at the appropriate time points.

Rescue oral analgesics: It is not ethical to refuse pain control medication to patients postoperatively as part of a clinical trial. A review of pror clinical trials indicated that NSAIDs are used for postoperative pain after PRK as rescue oral analgesics, similar to the Standard of care after PRK. Because the use of oral rescue medication may be a potential confounder of the pain VAS evaluation, three approaches were used when analyzing pain VAS scores to account for the influence of pain meds (assuming 4 hours of rescue medication effect): (1) any recorded VAS score within 4 hours after use of rescue medication was considered missing; (2) all the recorded VAS scores was used; and (3) any recorded VAS scores within 4 hours after rescue medication use was imputed by the record taken prior to the rescue medication.

Primary Efficacy Results

The mean VAS pain severity scores at 6 hours and 0-12 hours post-operatively are presented in Table 4 and Table 5, respectively, and shown in FIG. 1. The primary analysis was performed using the Primary PD analysis set.

The treatment differences in mean VAS pain severity scores at 6 hours and over 0-12 hours period post-operatively between compound I and Vehicle were statistically significant with p-values less than 0.10.

The model based means treatment difference (compound I—Vehicle) in VAS pain severity scores at 6 hours post-operatively was −11.1 (90% CI: (−17.54, −4.71; p=0.005) and at 0-12 hours period post-operatively was −8.56 (90% CI: (−14.29, −2.83; p=0.016). Thus, the primary efficacy objective of the study was met.

The treatment differences in mean VAS pain severity scores at 6 hours and over 0-12 hours period post-operatively between compound I and Vehicle were statistically significant with p-values less than 0.10.

TABLE 4 Mean VAS pain severity scores at 6-hours post- operatively (Primary PD analysis set) Comparison of model based means: Model estimated compound I vs. Vehicle mean* (SE) Diff compound I Vehicle (compound % P- (N = 30)^(#) (N = 29) I − Vehicle) Diff 90% CI value 34.63 (4.05) 45.76 (4.10) −11.1 −25% (−17.54, −4.71) 0.005 *To account for oral rescue medication (ORM) use, any recorded VAS pain scores taken up to 4 hours after the use of ORM was replaced with the VAS score recorded just before use of ORM, per FDA guidance 2014. ^(#)ePRO data from the first 10 patients (out 40 total) were not evaluable due to failure of the first vendor/ePRO device

TABLE 5 Mean VAS pain severity scores 0-12 hours post- operatively (Primary PD analysis set) Comparison of model based means: Model estimated compound I vs. Vehicle mean* (90% CI) Diff compound I Vehicle (compound % P- (N = 30) (N = 29) I − Vehicle) Diff 90% CI value 30.90 39.46 −8.56 −22% (−14.29, −2.83) 0.016 (24.04, 37.76) (32.54, 46.39) *To account for oral rescue medication (ORM) use, any recorded VAS pain scores taken up to 4 hours after the use of ORM was replaced with the VAS score recorded just before use of ORM, per FDA guidance 2014.

Secondary Efficacy Results

The number of patients who did not use oral rescue medication (ORM) was higher in compound I-treated eye compared to the Vehicle-treated eye at 0-6 hours, 0-12 hours and 0-24 hours post-operatively. After 36 hours post-operation, the same number of patients took ORM in compound I vs. Vehicle (Table 6).

TABLE 6 Summary of oral rescue medication use incidence (number of patients who did not use oral rescue medication) (Secondary PD analysis set) compound I 2.5% Vehicle N = 40 N = 40 Time interval n (%) n (%) p-value 0-6 hours post-operatively 23 (57.5%) 19 (47.5%) 0.2891 0-12 hours post-operatively 19 (47.5%) 16 (40.0%) 0.5811 0-24 hours post-operatively 16 (40.0%) 12 (30.0%) 0.3438 0-2 days post-operatively 11 (27.5%) 11 (27.5%) 1.0000 0-3 days post-operatively 11 (27.5%) 11 (27.5%) 1.0000 n: Number of patients who did not use oral rescue medication (ORM) * For the both treatment sequences column, n represents the number of patients who did not use oral rescue medication (ORM) in any treatment group.

Histogram of oral rescue medication (ORM) use incidence (number of patients who did not use ORM) is displayed in FIG. 2.

The summary and analysis of amount of ORM (number of pills per patient) is presented in Table 7.

TABLE 7 Summary of amount of oral rescue medication (Number of pills) (Secondary PD analysis set) % Change (Compound Time compound I Vehicle I − Vehicle)/ interval Statistics N = 40 N = 40 Vehicle 0-6 hours Mean (SD) 0.75 (1.032) 1.00 (1.132) −25% post- Range 0.0-4.0  0.0-4.0  operatively p-value 0.10* 0-12 hours Mean (SD) 1.40 (1.780) 1.65 (1.847) −15% post- Range 0.0-6.0  0.0-6.0  operatively p-value 0.26  0-24 hours Mean (SD) 2.35 (2.751) 2.80 (3.006) −16% post- Range 0.0-10.0 0.0-12.0 operatively p-value 0.05* 0-48 hours Mean (SD) 4.05 (4.466) 4.68 (5.225) −13% post-o Range 0.0-16.0 0.0-20.0 peratively p-value 0.05* 0-72 hours Mean (SD) 4.33 (4.896) 5.05 (5.574) −14% post- Range 0.0-21.0 0.0-22.0 operatively p-value 0.07* *Obtained from a Wilcoxon signed rank test N = total number of patients at each treatment *Statistical significance with p ≤ 0.10 (per primary endpoint power calculation)

As seen in Table 7 and FIG. 2, in every time interval during the study there was less ORM taken during compound I vs. Vehicle treatment

The summary and analysis of amount of ORM (mg/kg of body weight) is presented in Table 8.

In every time interval, amount of ORM (mg/kg of body weight) was less during compound I vs. Vehicle treatment (Table 8). During the periods 0-6 hours, 0-24 hours, 0-48 hours and 0-72 hours post-operatively the difference in milligrams per kilogram of body weight was statistically significant (p<0.10).

TABLE 8 Summary of amount of oral rescue medication (mg/kg of body weight) (Secondary PD analysis set) % Change (Compound Time Compound I Vehicle I − Vehicle)/ interval Statistics N = 40 N = 40 Vehicle 0-6 hours Mean (SD) 3.32 (4.684) 4.41 (5.038) −25% post-oper- Range 0.0-19.2 0.0-17.1 atively p-value 0.09* 0-12 hours Mean (SD) 6.10 (8.062) 7.39 (8.478) −17% post-oper- Range 0.0-28.7 0.0-28.7 atively p-value 0.21  0-24 hours Mean (SD) 10.17 (12.335) 12.41 (14.130) −18% post-oper- Range 0.0-47.9 0.0-57.5 atively p-value 0.05* 0-48 hours Mean (SD) 17.59 (19.850) 20.51 (23.991) −14% post-oper- Range 0.0-76.6 0.0-95.8 atively p-value 0.05* 0-72 hours Mean (SD) 18.70 (21.509) 22.06 (25.527) −15% post-oper- Range 0.0-87.4  0.0-105.4 atively p-value 0.06* *Obtained from a Wilcoxon signed rank test N = total number of patients at each treatment *Statistical significance with p ≤ 0.10 (per primary endpoint power calculation) Each acetaminophen/codeine tablet is considered as 330 mg in the calculation of amount (mg/kg of body weight).

VAS Pain Severity During the First 3 Days after PRK Surgery

After PRK surgery, patients reported statistically significantly lower VAS pain severity scores after treatment with compound I compared to Vehicle at p-value threshold 0.10 in 6 out of the 7 time points checked during the first 18 hours after surgery, starting with the hour 1 after surgery. The VAS pain severity scores were lower for compound I than Vehicle at all scheduled time points up to and including 36 hours after surgery. At all-time points from 36 hours until the end of the VAS collection period at 72 hours after PRK surgery, the difference between compound I VAS scores and Vehicle VAS scores was only marginally different, and there was no statistically significant difference between the scores at the p-value threshold of 0.10.

VAS Pain Severity Scores Before and After Instillation of Study Eye Drop

The mean changes in VAS scores from time points 6.5, 18.5 and 24.5 hours post-operative compared one-half hour prior to that and immediately before instillation of eye drops (namely at hours 6, 18 and 24) were −3.1, 2.8 and 1.3, respectively for compound I-treated eyes. For Vehicle-treated eyes the same differences were −5.6, 2.2 and −0.2, respectively.

Ocular Pain Assessment Survey (OPAS)

The OPAS is a validated instrument for quantifying and monitoring corneal and ocular surface pain and quality of life, developed in response to an identified need from a National Eye Institute Workshop in 2010. See Qazi et al., Ophthalmology July 123(7):1458-1468 (2016). The rating scale of the overall pain severity in the OPAS from Qazi et al. rated from 0 (no pain) to 10 (severe pain) or for frequency of symptoms from 0% (never) to 100% (all the time), as per the survey. The patients were asked to fill out the OPAS survey/questionnaire at Day 2, Day 4 (at the end of treatment period with study drug) and Day 8. Statistical analysis of OPAS results was not performed. Of the total of 27 OPAS questions, the results of seven questions are presented below.

In the questions of eye pain intensity during the previous 24 hours at the level of eye pain that is the most painful (question 4), level of pain that is the least painful (question 5) and level of eye pain in average (question 6) at Day 2 all 3 answers numerically favored compound I compared to Vehicle (FIG. 3A, FIG. 3B, FIG. 3C).

In the questions of how often eye pain was associated by the following symptoms: redness (question 22), burning (question 23), sensitivity to light (question 24) and tearing (question 25), all answers favored compound I compared to Vehicle (FIGS. 4A, 4B, 4C, and 4D). Thus, patients administered compound I exhibited lower levels of eye pain associated with redness, burning, sensitivity to light (photophobia), and tearing compared to patients administered placebo.

Summary Exploratory Ocular Results

-   -   Ocular Pain Assessment Survey (OPAS) showed better pain control         and quality of life patients during the compound I vs. the         Vehicle treatment period.     -   In the questions of eye pain intensity during the previous 24         hours at the level of eye pain that is the most painful         (question 4), level of pain that is the least painful         (question 5) and level of eye pain in average (question 6) at         day 2 all 3 answers favored compound I compared to Vehicle (FIG.         3A-3C).     -   In the questions of how often eye pain was associated by the         following symptoms: redness (question 22), burning (question         23), sensitivity to light (question 24) and tearing (question         25), all answers favored compound I compared to Vehicle (FIG.         4A-4D).     -   The VAS scores from time points 6.5, 18.5 and 24.5 hours         post-operatively compared one-half hour prior to that and         immediately before instillation of eye drops (namely at hours 6,         18 and 24) were −3.1, 2.8 and 1.3, respectively for compound         I-treated eyes. For Vehicle-treated eyes the same differences         were −5.6, 2.2 and −0.2, respectively.

Pharmacokinetics

Pharmacokinetic Assessments

Pharmacokinetic (PK) samples were collected at the time points defined in the visit schedule supra, with PK blood collection windows shown in Table 9.

TABLE 9 Permitted time window for PK blood collection Pre-dose Post-dose Within 90 min prior to dosing Within ±5 min of expected (sample numbers 101, 106, 107, time point relative to dose, up 112, 117 and 118) to 2 hours post-dose Within ±5 min from 72.25 to 74 hours (0.25 to 2 hours relative to timing of last dose)

All blood samples (3 mL) were taken from the arm by either direct venipuncture or an indwelling catheter inserted in a forearm vein. After each tube of blood was drawn, it was immediately inverted gently 8-10 times to ensure the mixing of tube contents with anticoagulant (3 mL K2 EDTA). Prolonged sample contact with the rubber stopper was avoided and the tubes were placed upright in a test tube rack surrounded by wet ice until centrifugation.

Within 30 minutes, the sample was centrifuged at about 5° C. for 10 minutes at approximately 2000 G (or the sample was placed on ice and centrifuged at room temperature). Immediately after centrifugation, the whole supernatant (approx. 1.5 mL) was transferred in the first 1.8 mL NUNC 2D barcoded cryovial. After mixing the plasma thoroughly, half of the plasma was transferred from the first cryovial to the second cryovial and the caps were secured. Appropriate PK cryolabels were attached to each cryovial and the labels were secured with clear tape. The cryovials were frozen immediately over dry ice then, kept frozen at ≤−20° C. until shipment to the central lab. The vials were shipped in biweekly batches.

Compound I was quantified in plasma using a validated LC-MS/MS method; the lower limit of quantification (LLOQ) was 0.05 ng/mL. Concentrations were expressed in ng per mL units. When feasible, bandage contact lenses (BCL) exposed to study drug were collected and analyzed for residual drug exposure after treatment (LLOQ: 5.00 ng/mL in 0.55 mL of extraction fluid, or 2.75 ng/BCL). Concentrations below the LLOQ were reported as “zero” and missing data were labeled as such.

The following PK parameters were determined as relevant using the actual recorded sampling times and non-compartmental method with Phoenix™ WinNonlin® (Version 6.4): Cmax, Tmax, AUClast (calculated), Clast and Tlast from the plasma concentration-time data. Pre-dose concentrations were determined by inspection at nominal 0, 24 and 72 hours. The linear trapezoidal rule was used for AUClast calculation. No PK parameters were calculated from the bandage contact lenses compound I concentration data.

Plasma Pharmacokinetics of Compound I

Arithmetic mean plasma concentration-time profiles and PK parameters of compound I are presented in FIG. 5A and FIG. 5B and Table 10, respectively.

After the unilateral topical ocular dose of compound I, absorption into the systemic circulation was rapid, with median Tmax of 0.459 hr and 0.467 hr after the first (Day 1; range 0.167-2.00 hr) and 13th (Day 4; range 0.00-2.08) doses, respectively. Cmax was determined and AUClast calculated for 34/40 patients on Day 1 and 33/40 (Cmax) or 31/40 (AUClast) patients on Day 4. All Day 1 pre-dose concentrations were below the limit of quantitation and imputed as 0.00 ng/mL. Trough (end of 6-hour dose interval and prior to next dose) mean concentration (CV %) prior to the 5th dose on Day 2 (24 hr post 1st dose; Day 2 time point of 0 h) was 1.25 ng/mL (54.9%), and slightly higher at 1.99 ng/mL (76.3%) prior to the 13th dose on Day 4 (72 hr post 1st dose; Day 4 time point of 0 h).

Concentrations were generally low, with observed Cmax ranging from 0.195 to 7.56 ng/mL, and AUClast from 0.261 to 14.5 ng*hr/mL, across 4 days of repeated QID dosing. Arithmetic mean Cmax (CV %) following the first dose on Day 1 was 0.454 ng/mL (49.9%) and 2.40 ng/mL (63.5%), i.e. 5.3-fold higher, after the 13th dose on Day 4. Corresponding mean AUClast (CV %) values were 0.638 ng*hr/mL (46.0%) and 4.38 ng*hr/mL (67.0%), representing a 6.9-fold increase over the 4 days.

TABLE 10 Summary statistics of compound I PK parameters after topical ocular administration of 2.5% compound I (PK analysis set) Profile Cmax Tmax AUClast day Statistic (ng/mL) (hr) (ng*hr/mL)¹ 1 N 34 34 34 Mean (SD) 0.454 (0.227) — 0.638 (0.293) CV % 49.9 — 46.0 Median 0.375 0.459 0.569 Min, Max 0.195, 1.05 0.167, 2.00 0.261, 1.58 4 N 33 33 31 Mean (SD) 2.40 (1.53) — 4.38 (2.94) CV % 63.5 — 67.0 Median 2.07 0.467 3.42 Min, Max 0.639, 7.56  0.00, 2.08  1.18, 14.5 ¹Median Tlast (range): Day 1, 2.00 hr (1.95-2.05 hr); Day 4, 2.00 hr (1.77-2.10 hr) Clast is not shown.

Bandage Contact Lens

Bandage Contact Lens (BCL) was collected from 40 patients on Day 4 of the dose administration and analyzed for compound I. Values from the three IMP non-compliant patients were excluded from BCL summary statistics, leaving 37 values evaluable, including one value from a patient without available plasma PK. The mean concentration of compound I (CV %) in 0.55 mL extraction fluid was 8500 ng/mL (73.1%), with a wide range of 284 to 22600 ng/mL. These concentrations translate to an estimated mean of 4680 ng/lens (0.55 mL×8500 ng/mL), and a range of 156 to 12400 ng/lens. The amount in BCL was very small in relation to the 0.925 mg dose of compound I administered: mean 0.51%, and range of 0.017% to 1.3% of dose. This indicates that the BCL absorbs and retains topical ocular compound I, but at negligible amounts compared to the topical ocular dose.

Summary Pharmacokinetic Results

-   -   Absorption of compound I into the systemic circulation was rapid         (median plasma Tmax was approximately 0.5 hours) after either         single (first dose) or repeated 4 times daily topical ocular         administration.     -   After both single and multiple topical ocular dose         administration of compound I, the systemic exposure was low,         ranging from 0.195 ng/mL to 7.56 ng/mL across 4 days of repeated         QID dosing, and showed moderate variability. Mean Cmax was 0.454         ng/mL after the first dose on Day 1 and 2.40 ng/mL after the         13th dose on Day 4.     -   The CV % values for Cmax and AUClast following single dose were         49.9% and 46.0%, respectively. The corresponding values after         repeated administration were 63.5% and 67.0%.     -   Mean Cmax after repeated administration (2.40 ng/mL) was         5.3-fold higher than after single dose on Day 1 (0.454 ng/mL).         Similarly, mean AUC last was 6.9-fold higher after repeated         versus single administration (4.38 versus 0.638 ng*hr/mL). These         data indicated accumulation over the 4 day period of 2.5%         compound I administration 4 times daily.     -   Bandage Contact Lens (BCL) was collected from 40 patients on Day         4 of dose administration. The mean concentration (CV %) in 0.55         mL extraction fluid was 8500 ng/mL (73.1%), which converts to an         estimated 4680 ng/lens. The amount in BCL was very small in         relation to the 0.925 mg dose of compound I administered: 0.51%,         and range of 0.017% to 1.3% of dose. This indicates that the BCL         absorbs and retains topical ocular compound I, but at negligible         amounts compared to the topical ocular dose.

Safety

Safety assessments consisted of collecting all AEs, SAES, with their severity and relationship to study drug. Table 11 includes a list of signs and symptoms which are common in the post-PRK surgery setting. Only signs and symptoms greater than the listed ranges of either severity or duration were reported as AEs.

TABLE 11 Signs and symptoms of PRK surgery which do not require reporting Expected Expected duration Sign/symptom severity after PRK surgery Corneal epithelial defect Mild to moderate 1 week Eye Edema Mild to moderate 1 week Eyelid Edema Mild to moderate 1 week Punctate Keratitis Mild to moderate 1 week Conjunctival Hyperemia Mild to moderate 1 week Reduction in BCVA of 10 Mild to moderate 1 month letters or more from baseline Eye pain Mild to moderate 1 week Ocular irritation/discomfort Mild to moderate 1 month Foreign body sensation Mild to moderate 1 month Lid margin irritation/crusting Mild to moderate 1 month Increased Lacrimation Mild to moderate 1 month Vision that is shadowy Mild to moderate 1 month Vision that is hazy Mild to moderate 1 month Blurred vision Mild to moderate 1 month Photophobia Mild to moderate 1 month Dry eye Mild to moderate 1 month Glare Mild to moderate 1 month Halos Mild to moderate 1 month

One week indicates resolution by the Day 8 post-op visit (Visit 6 in treatment period 1 or Visit 11 in period 2), including the allowable window. The table was constructed before initiating the study and with feedback from all primary investigators and surgeons based on their compiled experience with commonly encountered and expected clinical manifestations after standard PRK surgery.

One month indicates resolution by the EOS visit, or within 37 days post-surgery in cases where an EOS visit is not performed or there is more than one week between study surgeries.

Adverse events and serious adverse events included an assessment of both systemic and ocular assessments. Systemic safety assessments included regular assessments of height and weight, vital signs, reporting medication errors including misuse/abuse, pregnancy reporting and early phase safety monitoring. The misuse/abuse, pregnancy reporting and early phase safety monitoring were not assessed for the study. Ocular safety assessments included the following:

-   -   Best-corrected visual acuity (BCVA) and uncorrected visual         acuity (UCVA): Was measured at each visit using an ETDRS visual         acuity chart at 4 meters (13 feet) or 1 meter (for patients that         cannot read the 4 meter chart). The BCVA scoring was done based         on the number of correctly read letters plus 30. If visual         acuity was so poor that the patient could not read any of the         largest letters at 1 meter, count fingers and hand movement         vision and light perception was tested.     -   Intraocular Pressure (IOP): IOP measurements were conducted with         applanation tonometry or Tonopen.     -   Dilated fundus exam: The dilated fundus examination included         ophthalmoscopic assessments of the vitreous,         retina/macula/choroid, and optic nerve. Evaluations for retinal         tear/detachment, retinal hemorrhage, vitreous hemorrhage         density, vitreous haze grading and abnormal findings were done         and scored according to grading criteria.     -   Ocular hyperemia: Conjunctival redness of the bulbar conjunctiva         in each eye at the slit lamp according to the McMonnies redness         scale was graded. Hyperemia was assessed in four regions         (superior, inferior, temporal, nasal) of each eye with severity         scored 0-5 in each region.     -   Size of epithelial defect by slit lamp exam: Using an oblique         viewing angle relative to the source beam and a narrow slit         beam, the cornea was sectioned to visualize the vertical and         horizontal borders of the corneal wound. By adjusting the         calibrated slit beam width and height, the maximum horizontal         (wound width) and vertical dimensions (wound height) of the         surgical epithelial wound was estimated. The evaluation was         performed until wound closure and report of wound size as 0         horizontal and 0 vertical dimensions.     -   Slit-lamp biomicroscopy: Ocular signs (eyelids/conjunctiva,         cornea, lens, and iris/anterior chamber) was assessed in both         eyes by slit lamp biomicroscopy according to the grading         criteria.     -   Blink rate: A blink was defined as a bilateral paroxysmal         closure of the eyelids (duration <1 second) in the absence of a         provoking external stimulus. Each blink assessment lasted for 2         min (or as close to 2 minutes as possible with minimum time 1         minute) and the obtained blink rate was averaged to calculate         blink rate in blinks/min.     -   Tear production (Schirmer's test without anesthesia): The test         was performed without anesthetic in both eyes simultaneously.         Tear secretion was measured in millimeters of the length of         strip wetted by tears. The measurement was made to the nearest         whole number.     -   Corneal staining: This test was performed by gently touching the         wet end of an impregnated sodium fluorescein strip to the         inferior conjunctival sac. The strip was wetted with 1 drop of         sterile saline and flicked to remove excess saline. The patient         blinked several times to ensure dispersion of the dye throughout         the tear film prior to grading on a scale of 0-3 (0=Normal, No         staining; 1=Mild, Superficial stippling micropunctate staining;         2=Moderate, Macropunctate staining with some coalescent areas         and 3=Severe, Numerous coalescent macropunctate areas and/or         patches) for each of 5 zones (central plus 4 quadrants).

Safety Evaluation

There were no deaths or SAEs or discontinuation of the drug or discontinuation from the study due to AEs in the study. A total of 18 AEs were reported in 10 patients (25% of the 40 enrolled patients) of which twelve occurred after treatment with compound I, five after treatment with Vehicle and one occurred in one patient prior to dosing of the study drug. All AEs were either mild or moderate in severity.

A total of 10 patients (25%) experienced at least one treatment emergent AE, five patients experienced a single AE, and five patients experienced more than one AE. Five patients experienced an AE only during treatment with compound I, two patients experienced an AE only during treatment with Vehicle and three patients experienced an AE during treatment with both compound I and Vehicle. There was one AE (headache) that occurred prior to dosing of first study drug.

There were six ocular AEs in four patients (10% of the 40 enrolled patients), all of which were of mild severity (three eyes each treated with compound I and Vehicle). None of the AEs were suspected to be related to either study drug (compound I or Vehicle). Five of the six ocular AEs were thought to be related to the PRK procedure (two belonged to compound I treated eyes and 3 Vehicle treated eyes) by the Investigator.

There were twelve non-ocular AEs in seven patients (17.5%) (six eyes treated with compound I, two eyes treated with Vehicle and one patient during no drug period). Five AEs in four patients (10%) were of moderate severity (four eyes treated with compound I and one eye treated with Vehicle). The remaining AEs were of mild severity. None of the AEs were suspected to be related to compound I by the investigator.

Table 12 provides the overall incidence of adverse events.

TABLE 12 Overall incidence of AEs - number of events and number of patients (Safety analysis set) Compound I 2.5% Vehicle No drug* Total N = 40 N = 40 N = 40 N = 40 n (%) n (%) n (%) n (%) Patients with at 8 (20) 5 (12.5) 1 (2.5) 10 (25) least one AE Number of AEs 12  5 1 18  Patients with 3 (7.5) 3 (7.5) 0 4 (10) at least one ocular AE Number of 3 3 0 6 ocular AEs Patients with 6 (15) 2 (5) 1 (2.5) 7 (17.5) at least one non-ocular AE Number of 9 2 1 12  non-ocular AEs Number of mild 8 4 1 13  severity AEs Number of 4 1 0 5 moderate severity AEs Number of 0 0 0 0 severe AEs Number of 2 3 0 5 procedure- related AEs Number of drug- 0 0 0 0 related AEs An AE starting in one period and continuing into the next was counted only in the onset period. N = number of patients studied. *No drug, or baseline-emergent AE: AEs encountered after singing the informed consent and before the administration of any study drug (compound I or Vehicle).

Ocular Safety Assessments

Best-corrected visual acuity (BCVA) and uncorrected visual acuity (UCVA): The administration of compound I did not result in any trend or obvious difference between compound I and Vehicle-treated eyes throughout the study. The data therefore indicate that compound I reduces pain without adversely affecting BCVA and UCVA.

Intraocular pressure (IOP): No trend across the scheduled time points or obvious differences between compound I and Vehicle-treated eyes was observed throughout the study. At the end of study, there was slight increase (<5 mmHg) in mean IOP values compared to Baseline. The small change in mean scores during the study was not clinically significant.

Dilated fundus exam: No abnormal findings were reported by the Investigator across the scheduled time points for compound I and Vehicle-treated eyes.

Ocular hyperemia: A bar chart of ocular hyperemia over time for compound I and placebo treated eyes is provided in FIGS. 6A and 6B, respectively. FIGS. 6A and 6B indicate the Grade 4 and Grade 3 ocular hyperemia (as measured on the McMonnies scale) on Days 3 and 4, respectively. On Day 2 postoperatively (24 hours after PRK surgery) there was less grade 4 hyperemia (all quadrants) in compound I treated eyes compared to Vehicle treated eyes. In the superior quadrant the p-value for this difference was 0.04. On Day 3 (48 hours post-operative) less grade 3 hyperemia was observed in compound I treated eyes compared to Vehicle treated eyes. None of the observations were captured as AEs.

Size of epithelial defect by slit lamp exam: In order to assess the rate of wound healing after administration of compound I, the size of the epithelial defect in both compound I and Vehicle treated populations was measured. The elliptical area of epithelial wound size was calculated as follows: Area (mm2)=width×height×pi, from the width and height of the epithelial defect measured at the slit lamp. The difference in epithelial wound area between compound I and Vehicle was not noticeably different at any time point except at Day 2 post-PRK surgery (all p-values for the difference in area was >0.35). On Day 2 (24 hours post-operative), the difference in average epithelial defect area between patients treated with compound I vs. Vehicle was 11.23 mm2 (p value=0.034). This difference was not clinically significant in the immediate post-operative period. By Day 3 (48 hours post-operative) there was no difference between the compound I-treated and the Vehicle-treated eyes and the area of the wound was very small. On Day 4 (48 hours post-operative) almost all eyes had healed and there was no difference between compound I-treated and Vehicle treated eyes. Compound I showed no delay in wound healing compared to Vehicle.

FIG. 7 and Table 13 provide a comparison of the epithelial size defect of compound I treated eyes versus Vehicle treated eyes.

TABLE 13 Statistical analysis of epithelial defect size (Safety analysis set) Parameter (unit): Epithelial Wound Size (mm) Subcategory: Area (mm²) Raw mean (SD) Difference compound p- Visit compound I Vehicle I − Vehicle value* Day 1 220.15 (32.26) 217.16 (34.72) 2.98 (27.33) 0.494 Day 2 83.02 (32.08) 71.79 (26.96) 11.23 (32.30) 0.034 Day 3 6.75 (12.66) 5.73 (9.73) 1.02 (8.78) 0.467 Day 4 0.39 (2.04) 0.08 (0.50) 0.31 (2.11) 0.352 Day 8 0.00 (0.00) 0.00 (0.00) 0.00 (0.00) *Obtained from a paired t-test Epithelial defect size was calculated by slit lamp exam as the area of an ellipse calculated by maximum horizontal and vertical distance from center of epithelial defect. Area (mm²) = width*height*pi

Slit-lamp biomicroscopy: The slit-lamp biomicroscopic examination consisted of examination of ocular structures (eyelids/conjunctiva, cornea, iris/anterior chamber, lens, aqueous flare and aqueous inflammatory cell grade). No abnormalities were observed in ocular structures of aqueous flare and aqueous inflammatory cell grade, iris/anterior chamber and lens in patients treated with both compound I and Vehicle across the scheduled time points.

Blink rate: There were fluctuations in the mean blink rate; however, no trend across the scheduled time points or obvious differences between blink rate after compound I and Vehicle treatment was observed throughout the study. At the end of study, no clinically relevant changes were observed in blink rate compared to Baseline.

Corneal staining: Most of the patients had normal (grade 0) degree of staining measured on Baseline, Day 8 and EOS visits. No clinical differences were observed in the corneal staining between the eyes treated with compound I versus Vehicle, at either the baseline, or the Day 8 or the EOS visit.

Vital signs, physical findings and other observations related to safety: The vital sign parameters (systolic and diastolic blood pressures, pulse rate and body temperature) were within the normal range for all patients during the study. No AEs related to vital signs were observed. Electrocardiogram and special safety topics were not conducted and assessed (as per protocol).

Summary of Safety Results

-   -   There were no deaths, or serious or severe AEs, treatment         discontinuations or study discontinuations reported in this         study.     -   No AEs were evaluated to be related to study drug (either         compound I or Vehicle). Eight of 40 patients and five of 40         patients developed AEs after compound I and Vehicle treatment,         respectively. All Ocular AEs were mild and balanced between         compound I and Vehicle with the vast majority being well known         AEs related to the PRK procedure.     -   There were no observed clinically meaningful differences in         safety between compound I and Vehicle.     -   Compound I showed no delay in wound healing compared to Vehicle.     -   Fewer compound I-treated eyes showed severe conjunctival         hyperemia on Day 2 (24 hours post-operative) compared to         Vehicle-treated eyes.     -   There were no clinically relevant changes observed for BCVA,         IOP, slit-lamp biomicroscopy, dilated eye exam, blink rate, tear         production, corneal staining, or vital signs after compound I         administration compared to Vehicle.

The incidence of AEs by preferred term is presented in Table 14.

TABLE 14 Incidence of AEs by preferred term - n (percent) of patients (Safety analysis set) Compound I 2.5% Vehicle No drug (prior to drug)* N = 40 n (%) N = 40 n (%) N = 40 n (%) Total Procedure Procedure Procedure N = 40 AEs by preferred term n (%) Severity related n (%) Severity related n (%) Severity related n (%) Patients with at least one AE 8 (20.0) 5 (12.5) 1 (2.5) 10 (25) Ocular Corneal Infiltrate 0 1 (2.5) mild yes 0 1 (2.5) AEs Corneal Opacity 1 (2.5) mild yes 1 (2.5) mild yes 0 1 (2.5) Punctate Keratitis 1 (2.5) mild yes 1 (2.5) mild yes 0 1 (2.5) Posterior Vitreous 1 (2.5) mild no 0 0 1 (2.5) Detachment Non- Headache 1 (2.5) mild no 1 (2.5) moderate no 1 (2.5) mild no 3 (7.5) ocular Arthralgia 1 (2.5) mild no 0 0 1 (2.5) AEs Nasopharyngitis 2 (5.0) mild, mild no 0 0 2 (5.0) Oropharyngeal Pain 1 (2.5) mild no 0 0 1 (2.5) Tinnitus 0 1 (2.5) mild no 0 1 (2.5) Sinus Congestion 1 (2.5) moderate no 0 0 1 (2.5) Sinusitis 1 (2.5) moderate no 0 0 1 (2.5) Pyrexia 1 (2.5) moderate no 0 0 1 (2.5) Vomiting 1 (2.5) moderate no 0 0 1 (2.5) An adverse event starting in one period and continuing into the next is counted only in the onset period. N = number of patients studied. n = number of patients with at least one AE in the category. *No drug, or baseline-emergent AE: AEs encountered after singing the informed consent and before the administration of any study drag (compound I or Vehicle).

All publications and patent documents cited herein are incorporated herein by reference as if each such publication or document was specifically and individually indicated to be incorporated herein by reference. The present invention and its embodiments have been described in detail. However, the scope of the present invention is not intended to be limited to the particular embodiments of any process, manufacture, composition of matter, compounds, means, methods, and/or steps described in the specification. Various modifications, substitutions, and variations can be made to the disclosed material without departing from the spirit and/or essential characteristics of the present invention. Accordingly, one of ordinary skill in the art will readily appreciate from the invention that later modifications, substitutions, and/or variations performing substantially the same function or achieving substantially the same result as embodiments described herein may be utilized according to such related embodiments of the present invention. Thus, the following claims are intended to encompass within their scope modifications, substitutions, and variations to processes, manufactures, compositions of matter, compounds, means, methods, and/or steps disclosed herein. The claims should not be read as limited to the described order or elements unless stated to that effect. It should be understood that various changes in form and detail may be made without departing from the scope of the appended claims. 

What is claimed is:
 1. A method of reducing chronic ocular surface pain in a subject in need thereof, comprising ocularly administering an effective amount of 4-(7-Hydroxy-2-isopropyl-4-oxo-4H-quinazolin-3-yl)-benzonitrile (Formula I) having structure:

or a salt, solvate, polymorph, or co-crystal thereof to the subject, wherein the compound of Formula I is administered to the subject at a concentration of about 0.5% w/v to about 3.5% w/v.
 2. The method of claim 1, comprising administering the compound of formula I at a concentration of about 0.5% w/v, about 1.0% w/v, about 1.5% w/v, about 2.0% w/v, about 2.5% w/v, about 3.0% w/v, or about 3.5% w/v.
 3. The method of claim 1, comprising administering the compound of formula I at a total daily dose per eye of about 0.5 to about 3.5 mg, or about 0.5 mg, about 1.0 mg, about 1.5 mg, about 2.0 mg, about 2.5 mg, about 3.0 mg, or about 3.5 mg.
 4. The method according to claim 1, wherein the subject suffers from one or more of dry eye disease, Sjogren's Syndrome, conjunctivitis, Map-Dot-Fingerprint Dystrophy, acanthamoeba, fibromyalgia, Meibomian gland dysfunction, thyroid eye disease, rosacea, ptosis, keratoconus, ocular pain syndrome, Steven-Johnson's syndrome, corneal epitheliopathies, corneal neuropathies, corneal dystrophies, epithelial basement membrane dystrophy, corneal erosions or abrasions, ocular surface diseases, blepharitis, graft vs host disease, meibomitis, glaucoma, conjunctivochalasis, keratopathis keratitis, iritis, episclentis, corneal surgery, multiple sclerosis, trichiasis, pterygium, neuralgia, xerophthalmia, patients recovering from neurotrophic keratitis, or ocular pain persisting for at least three months after photorefractive keratectomy (PRK) surgery or laser-assisted in situ keratomileusis (LASIK) surgery.
 5. The method according to claim 1, wherein the administration results in a reduction in the subject's pain of at least about 10%, at least about 15%, at least about 20%, or at least about 25%, compared to a placebo, wherein the reduction in the pain score arises from the difference in pain scores prior to and after administration of compound I to the subject.
 6. The method according to claim 5, wherein the reduction in pain score occurs within about half hour after administration of compound I to the subject.
 7. The method according to claim 1, wherein the administration of compound I to the subject results in reduced incidence of at least about 10% in one or more of ocular dryness, ocular discomfort, ocular hyperemia, ocular burning or stinging, grittiness or foreign body sensation, or photophobia. 